ADS5294IPFPT

Product Folder Order Now Support & Community Tools & Software Technical Documents ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 ADS5294 Octal-Channel 14-Bit 80-MSPS High-SNR and Low-Power ADC 1 Features 3 Description • • The ADS5294 is a low-power 80-MSPS 8-Channel ADC that uses CMOS process technology and innovative circuit techniques. Low power consumption, high SNR, low SFDR, and consistent overload recovery allow users to design highperformance systems. • • • LGND LVDD AVDD Simplified Block Diagram 1 of 8 Channels OUTxA_P INxP INxN 14 bit 14 BIT ADC ADAC SAMPLING CIRCUIT DIGITAL PROCESSING BLOCK OUTxA_N SERIALIZER OUTxB_P OUTxB_N LCLKP CLKP LCLKN CLOCKGEN CLKN PLL ACLKP SYNC ACLKN CONTROL INTERFACE REFERENCE SDOUT CSZ SDATA ADS5294 SCLK 2 Applications BODY SIZE (NOM) 12.00 mm × 12.00 mm (1) For all available packages, see the orderable addendum at the end of the data sheet. PD • PACKAGE HTQFP (80) RESET • • • • PART NUMBER ADS5294 AGND • Device Information(1) VCM • The digital processing block of the ADS5294 integrates several commonly used digital functions for improving system performance. The device includes a digital filter module that has built-in decimation filters (with lowpass, highpass and bandpass characteristics). The decimation rate is also programmable (by 2, by 4, or by 8). This rate is useful for narrow-band applications, where the filters are used to conveniently improve SNR and knock-off harmonics, while at the same time reducing the output data rate. The device includes an averaging mode where two channels (or even four channels) are averaged to improve SNR. REFT • Maximum Sample Rate: 80 MSPS/14-Bit High Signal-to-Noise Ratio – 75.5-dBFS SNR at 5 MHz / 80 MSPS – 78.2-dBFS SNR at 5 MHz / 80 MSPS and Decimation Filter Enabled – 84-dBc SFDR at 5 MHz / 80 MSPS Low Power Consumption – 58 mW/CH at 50 MSPS – 77 mW/CH at 80 MSPS (2-LVDS Wire Per Channel) Digital Processing Block – Programmable FIR Decimation Filter and Oversampling to Minimize Harmonic Interference – Programmable IIR High-Pass Filter to Minimize DC Offset – Programmable Digital Gain: 0 dB to 12 dB – 2-Channel or 4-Channel Averaging Flexible Serialized LVDS Outputs: – One or Two Wires of LVDS Output Lines Per Channel Depending on ADC Sampling Rate – Programmable Mapping Between ADC Input Channels and LVDS Output Pins-Eases Board Design – Variety of Test Patterns to Verify Data Capture by FPGA/Receiver Internal and External References 1.8-V Operation for Low Power Consumption Low-Frequency Noise Suppression Recovery From 6-dB Overload Within 1 Clock Cycle Package: 12-mm × 12-mm 80-Pin QFP REFB 1 Ultrasound and Sonar Imaging Communication Applications Multi-channel Data Acquisition 1 An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA. ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Table of Contents 1 2 3 4 5 6 7 8 Features .................................................................. Applications ........................................................... Description ............................................................. Revision History..................................................... Description (continued)......................................... Device Comparison Table..................................... Pin Configuration and Functions ......................... Specifications......................................................... 1 1 1 2 5 6 7 9 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 Absolute Maximum Ratings ...................................... 9 ESD Ratings.............................................................. 9 Recommended Operating Conditions..................... 10 Thermal Information ................................................ 10 Electrical Characteristics Dynamic Performance .... 11 Digital Characteristics ............................................. 12 Timing Requirements .............................................. 13 LVDS Timing at Different Sampling Frequencies — 2-Wire Interface, 7x-Serialization, Digital Filter Disabled .................................................................. 14 8.9 LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Digital Filter Disabled .................................................................. 14 8.10 Serial Interface Timing Requirements................... 15 8.11 Reset Timing ......................................................... 15 8.12 LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 2 Filter Enabled .......................................................... 16 8.13 LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 4 Filter Enabled .......................................................... 16 8.14 LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 8 Filter Enabled .......................................................... 16 8.15 Typical Characteristics .......................................... 22 9 Detailed Description ............................................ 28 9.1 9.2 9.3 9.4 9.5 9.6 Overview ................................................................. Functional Block Diagram ....................................... Feature Description................................................. Device Functional Modes........................................ Programming........................................................... Register Maps ......................................................... 28 29 30 37 37 40 10 Application and Implementation........................ 64 10.1 Application Information.......................................... 64 10.2 Typical Application ............................................... 65 11 Power Supply Recommendations ..................... 69 12 Layout................................................................... 69 12.1 Layout Guidelines ................................................. 69 12.2 Layout Example .................................................... 70 13 Device and Documentation Support ................. 71 13.1 13.2 13.3 13.4 13.5 13.6 Device Support...................................................... Documentation Support ........................................ Community Resources.......................................... Trademarks ........................................................... Electrostatic Discharge Caution ............................ Glossary ................................................................ 71 73 73 73 73 73 14 Mechanical, Packaging, and Orderable Information ........................................................... 73 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision D (September 2015) to Revision E Page • Added The maximum limit used for the LVDD current at –40°C is 132 mA table note ....................................................... 12 • Added bypass decimation values to the DATA_RATE, FILTERn_RATE, and FILTERn_COEFF_SET columns ............... 33 • Changed D15 value of ADDR. (HEX) 28 to X ...................................................................................................................... 41 • Changed this to the byte-wise for clarification...................................................................................................................... 41 • Changed this to the word-wise for clarification..................................................................................................................... 41 • Changed D15 value to 1 in Bit-Byte-Word Wise Output table.............................................................................................. 48 • Added DATA_RATE>, FILTERn_RATE, and FILTERn_COEFF_SET values to the bypass decimation row in the Digital Filters table ................................................................................................................................................................ 55 Changes from Revision C (September 2013) to Revision D Page • Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section .............................. 1 • Added "Sonar Imaging" in Applications ................................................................................................................................. 1 • Updated Pinout. ...................................................................................................................................................................... 7 • Added text note 2 to Figure 1 .............................................................................................................................................. 17 • Added a text note to Figure 44. ........................................................................................................................................... 30 2 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 • Corrected typo in Table 1 ..................................................................................................................................................... 33 • Added note to EN_2WIRE bit. .............................................................................................................................................. 44 • Corrected typo in Table 17 ................................................................................................................................................... 55 Changes from Revision B (July 2012) to Revision C Page • Added cross-reference link for VCM pin................................................................................................................................. 7 • Added note for REFB pin under INT/EXT reference modes. ................................................................................................. 8 • Added note for REFT pin under INT/EXT reference modes. ................................................................................................. 8 • Changed the maximum rating of digital input pins RESET, SCLK, SDATA, SYNC, PD, CSZ to 3.6V.................................. 9 • Added test condition "Digital Filter Disabled" and changed "LVDS output rate" to "ADC CLK Frequency" in LVDS Timing at Different Sampling Frequencies — 2-Wire Interface, 7x-Serialization, Digital Filter Disabled . ........................... 14 • Added test condition "Digital Filter Disabled" and changed "LVDS output rate" to "ADC CLK Frequency" in LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Digital Filter Disabled . ......................... 14 • Added note after LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Digital Filter Disabled : The above LVDS timing spec is only valid when digital filters are disabled... ........................................... 14 • Added LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 2 Filter Enabled ................................................................................................................................................................................ 16 • Added LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 4 Filter Enabled ................................................................................................................................................................................ 16 • Added LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 8 Filter Enabled ................................................................................................................................................................................ 16 • Added a note related to EN_CUSTOM_FILT and changed formats in Table 9. .................................................................. 33 • Added PLL Operation Versus LVDS Timing before APPLICATION INFORMATION section ............................................ 35 • Added a note link to Reg.0x38 . ........................................................................................................................................... 44 • Changed 0xF[15] to 0xF0[15] in the description of Reg.0x42. ............................................................................................. 44 • Changed the Reg.0x46[11:8] formatting. ............................................................................................................................. 44 • Corrected the EN_RAMP address from 0x24 to 0x25 in the section of LVDS test patterns. ............................................. 47 • Changed "Note that these bits are functional only when the GLOBAL_EN_FILTER gets set to 1" to " Note that these bits are functional only when the GLOBAL_EN_FILTER gets set to 1 and USE_FILTERn bit is set to 1” in the section of Decimation Filter,. ............................................................................................................................................... 54 • Added a note related to EN_CUSTOM_FILT and changed formats inTable 17 . ................................................................ 55 • Changed Equation (5). ......................................................................................................................................................... 59 • Added register address in Table 23. .................................................................................................................................... 59 • Revised Figure 63 and moved the 2pF cap to the left hand side of the resistors. .............................................................. 66 • Added a note regarding the location of LVDS Rterm in the section of Input clock. ............................................................ 67 Changes from Revision A (November 2011) to Revision B Page • Changed the location of OUT A and OUT B in Figure 5 and Figure 6................................................................................. 20 • Added Figure 45 ................................................................................................................................................................... 31 • Replaced Table 9 (Decimation Filter Modes) with new Table 1 - Digital Filters................................................................... 33 • Deleted section: Synchronization Pulse ............................................................................................................................... 35 • Added EN_HIGH_ADDRS to Table 3................................................................................................................................... 40 • Moved EN_EXT_REF From: 0x0F To: 0xF0 in Table 3....................................................................................................... 45 • Added the section BIT-BYTE-WORD WISE OUTPUT. Added Figure 53 and Figure 54..................................................... 48 • Added section DIGITAL PROCESSING BLOCKS ............................................................................................................... 49 • Replaced Table 5 and Table 6 with new Table 17 - Digital Filters....................................................................................... 55 • Changed the SYNCHRONIZATION PULSE section ............................................................................................................ 58 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 3 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 • www.ti.com Added the External Reference Mode of Operation section.................................................................................................. 59 Changes from Original (November 2011) to Revision A • 4 Page Changed From: Product Preview To: Production................................................................................................................... 1 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 5 Description (continued) Serial LVDS outputs reduce the number of interface lines and enable the highest system integration. The digital data from each channel ADC is output over one or two wires of LVDS output lines depending on the ADC sampling rate. This 2-wire interface maintains a low serial-data rate, allowing low-cost FPGA-based receivers to be used even at a high sample rate. The ADC resolution is programmed to 12-bit or 14-bit through registers. A unique feature is the programmable-mapping module that allows flexible mapping between the input channels and the LVDS output pins. This module greatly reduces the complexity of LVDS-output routing, and by reducing the number of PCB layers, potentially results in cheaper system boards. The device integrates an internal reference trimmed to accurately match across devices. Internal reference mode achieves the best performance. External references can also drive the device. The device is available in a 12-mm × 12-mm 80-pin QFP package. The device is specified over a –40°C to 85°C operating temperature range. ADS5294 is completely pin-to-pin and register compatible to ADS5292. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 5 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 6 Device Comparison Table PACKAGE BODY SIZE (NOM) ADS5294 DEVICE Octal-channel, 14-bit, 80-MSPS ADC, 75-dBFS SNR, 77 mW/ch HTQFP (80) 14.00 mm × 14.00 mm ADS5292 Octal-channel, 12-bit, 80-MSPS ADC, 70-dBFS SNR, 66 mW/ch HTQFP (80) 14.00 mm × 14.00 mm ADS5295 Octal-channel, 12-bit, 100-MSPS ADC, 70.6-dBFS SNR, 80 mW/ch HTQFP (80) 14.00 mm × 14.00 mm ADS5296A 10-bit, 200-MSPS, 4-channel, 61-dBFS SNR, 150-mW/ch and 12-bit, 80-MSPS, 8-channel, 70-dBFS SNR, 65-mW/ch ADC VQFN (64) 9.00 mm × 9.00 mm AFE5801 8-channel variable-gain amplifier (VGA) with octal high-speed ADC, 5.5 nV/√Hz, 12 bits, 65 MSPS, 65 mW/ch VQFN (64) 9.00 mm × 9.00 mm AFE5803 8-channel AFE, 0.75 nV/√Hz, 14 and 12 bits, 65 MSPS, 158 mW/ch NFBGA (135) 15.00 mm × 9.00 mm AFE5804 8-channel AFE, 1.23 nV/√Hz, 12 bits, 50 MSPS, 101 mW/ch NFBGA (135) 15.00 mm × 9.00 mm AFE5805 8-channel AFE, 0.85 nV/√Hz, 12 bits, 50 MSPS, 122 mW/ch NFBGA (135) 15.00 mm × 9.00 mm AFE5807 8-channel AFE with passive CW mixer, 1.05 nV/√Hz, 12 bits, 80 MSPS, 117 mW/ch NFBGA (135) 15.00 mm × 9.00 mm AFE5808A 8-channel AFE with passive CW mixer, 0.75 nV/√Hz, 14 and 12 bits, 65 MSPS, 158 mW/ch NFBGA (135) 15.00 mm × 9.00 mm AFE5809 8-channel AFE with passive CW mixer, and digital I/Q demodulator, 0.75 nV/√Hz, 14 and 12 bits, 65 MSPS, 158 mW/ch NFBGA (135) 15.00 mm × 9.00 mm AFE5812 Fully integrated, 8-channel AFE with passive CW mixer, and digital I/Q demodulator, 0.75 nV/√Hz, 14 and 12 bits, 65 MSPS, 180 mW/ch NFBGA (135) 15.00 mm × 9.00 mm AFE5818 16-Channel AFE with 124-mW/Channel, 0.75-nV/√Hz Noise, 14-Bit, 65-MSPS or 12Bit, 80-MSPS ADC, and Passive CW Mixer NFBGA (289) 15.00 mm × 15.00 mm AFE5816 16-channel AFE with 90-mW/channel, 1-nV/√Hz noise, 14-bit, 65-MSPS or 12-bit, 80MSPS ADC and passive CW mixer NFBGA (289) 15.00 mm × 15.00 mm AFE5851 16-channel VGA with high-speed ADC, 5.5 nV/√Hz, 12 bits, 32.5 MSPS, 39 mW/ch VQFN (64) 9.00 mm × 9.00 mm VCA8500 8-channel, ultralow-power VGA with low-noise pre-amp, 0.8 nV/√Hz, 65 mW/ch VQFN (64) 9.00 mm × 9.00 mm VCA5807 8-channel voltage-controlled amplifier with passive CW mixer, 0.75 nV/√Hz, 99 mW/ch HTQFP (80) 14.00 mm × 14.00 mm VQFN (64) 9.00 mm × 9.00 mm PGA5807A 6 DESCRIPTION Integrated 8-channel AFE with LNA, PGA, and LPF,2.1 nV/√Hz, 60 mW/ch Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 7 Pin Configuration and Functions 67 66 IN8P 68 AGND 69 IN8N 70 SYNC 71 SDOUT 72 NC 73 AVDD 74 VCM 75 REFB 76 AVDD 77 REFT SDATA 78 CLKP SCLK 79 CLKN IN1P 80 1 CSZ IN1N IN2P AVDD AGND PFP Package 80-PIN TQFP With Thermal Pad Top View 65 64 63 62 61 60 IN7N IN2N 2 59 IN7P AGND 3 58 AGND IN3P 4 57 IN6N IN3N 5 56 IN6P AGND 6 55 AGND Thermal Pad (Can be tied to AGND) IN4P 7 54 IN5N IN4N 8 53 IN5P AVDD 9 52 AVDD PD 10 LVDD 11 LGND 12 ADS529X 80 TQFP 51 RESET 50 LGND 49 LVDD OUT1A_P 13 48 OUT8A_N OUT1A_N 14 47 OUT8A_P 28 29 30 31 32 33 34 35 36 37 38 39 41 40 OUT6A_N 27 OUT6A_P 26 OUT6B_N 25 OUT5B_N 24 LCLKP 23 OUT6B_P OUT7B_P 22 OUT5A_N 20 21 OUT5A_P OUT2B_N LCLKN OUT2B_P OUT7B_N OUT5B_P OUT7A_P 42 ACLKN 43 19 ACLKP 18 OUT4B_N OUT2A_N OUT4B_P OUT7A_N OUT4A_N OUT2A_P 44 OUT4A_P OUT8B_P 17 OUT3B_N OUT8B_N 45 OUT3B_P 46 16 OUT3A_P 15 OUT3A_N OUT1B_P OUT1B_N Pin Functions PIN NAME DESCRIPTION NO. AVDD 9, 52, 66, 71, 74 AGND 3, 6, 55, 58, 61, 80 Analog power supply, 1.8 V Analog ground VCM 68 Common-mode output pin, 0.95-V output. This pin can be configured as the external reference voltage (1.5 V) input pin as well. See Reg 0x42 and External Reference Mode of Operation. CLKN 73 Negative differential clock –Tie CLKN to GND for single-ended clock CLKP 72 Positive differential clock IN1P, IN1N 78, 79 Differential input signal, Channel 1 IN2P, IN2N 1, 2 Differential input signal, Channel 2 IN3P, IN3N 4, 5 Differential input signal, Channel 3 IN4P, IN4N 7, 8 Differential input signal, Channel 4 IN5P, IN5N 53, 54 Differential input signal, Channel 5 IN6P, IN6N 56, 57 Differential input signal, Channel 6 IN7P, IN7N 59, 60 Differential input signal, Channel 7 IN8P, IN8N 62, 63 Differential input signal, Channel 8 LCLKP, LCLKN 31, 32 Differential LVDS bit clock (7X) ACLKP, ACLKN 29, 30 Differential LVDS frame clock (1X) Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 7 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Pin Functions (continued) PIN NAME DESCRIPTION NO. OUT1A_P, OUT1A_N 13, 14 Differential LVDS data output, wire 1, channel 1 OUT1B_P, OUT1B_N 15, 16 Differential LVDS data output, wire 2, channel 1 OUT2A_P, OUT2A_N 17, 18 Differential LVDS data output, wire 1, channel 2 OUT2B_P, OUT2B_N 19, 20 Differential LVDS data output, wire 2, channel 2 OUT3A_P, OUT3A_N 21, 22 Differential LVDS data output, wire 1, channel 3 OUT3B_P, OUT3B_N 23, 24 Differential LVDS data output, wire 2, channel 3 OUT4A_P, OUT4A_N 25, 26 Differential LVDS data output, wire 1, channel 4 OUT4B_P, OUT4B_N 27, 28 Differential LVDS data output, wire 2, channel 4 OUT5A_P, OUT5A_N 35, 36 Differential LVDS data output, wire 1, channel 5 OUT5B_P, OUT5B_N 33, 34 Differential LVDS data output, wire 2, channel 5 OUT6A_P, OUT6A_N 39, 40 Differential LVDS data output, wire 1, channel 6 OUT6B_P, OUT6B_N 37, 38 Differential LVDS data output, wire 2, channel 6 OUT7A_P, OUT7A_N 43, 44 Differential LVDS data output, wire 1, channel 7 OUT7B_P, OUT7B_N 41, 42 Differential LVDS data output, wire 2, channel 7 OUT8A_P, OUT8A_N 47, 48 Differential LVDS data output, wire 1, channel 8 OUT8B_P, OUT8B_N 45, 46 Differential LVDS data output, wire 2, channel 8 PD 10 Power-down control input. Active High. The pin has an internal 220-kΩ pulldown resistor. REFB 69 Negative reference input and output. Internal reference mode: Reference bottom voltage (0.45 V) is output on this pin. A decoupling capacitor is not required on this pin. External reference mode: Reference bottom voltage (0.45 V) must be externally applied to this pin. Please see External Reference Mode of Operation. REFT 70 Positive reference input and output. Internal reference mode: Reference top voltage (1.45 V) is output on this pin. A decoupling capacitor is not required on this pin. External reference mode: Reference top voltage (1.45 V) must be externally applied to this pin. Please see External Reference Mode of Operation. RESET 51 Active HIGH RESET input. The pin has an internal 220-kΩ pulldown resistor. SCLK 77 Serial clock input. The pin has an internal 220-kΩ pulldown resistor. SDATA 76 Serial data input. The pin has an internal 220-kΩ pulldown resistor. SDOUT 64 Serial data readout. This pin is in the high-impedance state after reset. When the bit is set, the SDOUT pin becomes active. SDOUT is a CMOS digital output running from the AVDD supply. CSZ 75 Serial enable chip select – active-low digital input SYNC 65 Input signal to synchronize channels and chips when used with reduced output data rates. If it is not used, add a ≤ 10-KΩ pulldown resistor. LVDD 11, 49 Digital and I/O power supply, 1.8 V LGND 12, 50 Digital ground NC 8 67 No Connection. Must leave floated Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 8 Specifications 8.1 Absolute Maximum Ratings over operating free-air temperature range (unless otherwise noted) (1) Supply voltage MIN MAX UNIT AVDD –0.3 2.2 V LVDD –0.3 2.2 V Between AGND and LGND –0.3 0.3 V –0.3 min[2.2, AVDD+0.3] V –0.3 3.6 V –0.3 min[2.2, AVDD+0.3] V –0.3 min[2.2, LVDD+0.3] V 105 °C At analog inputs Voltage At digital inputs, RESET, SCLK, SDATA, SYNC, PD, CSZ At CLKN, CLKP (2), At digital outputs Maximum junction temperature (TJ), any condition Operating temperature –40 85 °C Storage temperature, Tstg –55 150 °C (1) (2) Stresses above those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute maximum rated conditions for extended periods may degrade device reliability. When AVDD is turned off, TI recommends to switch off the input clock (or ensure the voltage on CLKP, CLKN is < |0.3V|). This prevents the ESD protection diodes at the clock input pins from turning on. 8.2 ESD Ratings VALUE V(ESD) (1) (2) Electrostatic discharge Human body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1) ±1000 Charged-device model (CDM), per JEDEC specification JESD22-C101 (2) ±250 UNIT V JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 9 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 8.3 Recommended Operating Conditions MIN NOM MAX UNIT AVDD Analog supply voltage 1.7 1.8 1.9 V LVDD 1.7 1.8 1.9 V SUPPLIES Digital supply voltage ANALOG INPUTS/OUTPUTS Differential input voltage range 2 Input common-mode voltage VPP 0.95 ± 0.05 V REFT External reference mode 1.45 V REFB External reference mode 0.45 V Common-mode voltage output 0.95 V VCM External Reference mode Input Maximum Input Frequency (1) 2 VPP amplitude 1.5 V 80 MHz CLOCK INPUTS ADC Clock input sample rate 10 Input Clock amplitude differential (V(CLKP) – V(CLKN)) peak-to-peak VIL Sine wave, AC-coupled 0.2 1.5 LVPECL, AC-coupled 0.2 1.6 LVDS, AC-coupled 0.2 0.7 V >1.5 Input clock duty cycle 35% 50% MSPS VPP DC 15 MHz fSCLK SCLK frequency (= 1 / tSCLK) tSLOADS CS to SCLK set-up time 33 ns tSLOADH SCLK to CS hold time 33 ns tDS SDATA set-up time 33 ns tDH SDATA hold time 33 ns 8.11 Reset Timing The table shows typical values at 25°C. MIN and MAX values are across the full temperature range TMIN = –40°C to TMAX = 85°C (unless otherwise noted). See Figure 1 MIN t1 Power-on delay Delay from power up of AVDD and LVDD to RESET pulse active t2 Reset pulse duration Pulse duration of active RESET signal t3 Register write delay Delay from RESET disable to CSZ active TYP MAX 1 50 Product Folder Links: ADS5294 ms ns 100 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated UNIT ns 15 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 8.12 LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 2 Filter Enabled See (1) (2) (3) ADC CLK Frequency (MSPS) Set-up Time (tsu), ns Hold Time (tH), ns tPROG = (6 / 7) × T + tdelay, ns (4) Fs = 1 / T Data Valid to ZeroCrossing of LCLKP (both edges) Zero-Crossing of LCLKP to Data Becoming Invalid (both edges) tPROG = delay from input clock zero-cross rising edge to frame clock zero cross (rising edge) MIN (1) (2) (3) (4) MIN TYP MAX 80 0.43 TYP MAX 0.54 MIN TYP MAX 7.5 9 10.5 60 0.54 0.9 7.5 9 10.5 40 1.1 1.45 7.5 9 10.5 Bit clock and Frame clock jitter has been included in the Set-up and hold timing. The LVDS timing depends on the state of the internal PLL. Use Table 3 to configure the PLL when decimation by two is enabled.. For any given ADC input clock frequency, TI recommends to use the highest PLL state to get the best set-up time. The timing numbers are specified under this condition. For example, for a 40-MSPS input clock frequency, use PLL state 3 to get set-up time ≥ 1.1 ns. PLL state 2 can also be used at 40 MSPS, however, the set-up time degrades by 100 to 200 ps (while the hold time improves by a similar amount). Values below correspond to tdelay, not tPROG 8.13 LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 4 Filter Enabled See (1) (2) (3) ADC CLK Frequency (MSPS) Set-up Time (tsu), ns Hold Time (tH), ns tPROG = (8 / 7) × T + tdelay, ns (4) Fs = 1 / T Data Valid to ZeroCrossing of LCLKP (both edges) Zero-Crossing of LCLKP to Data Becoming Invalid (both edges) tPROG = delay from input clock zero-cross rising edge to frame clock zero cross (rising edge) MIN (1) (2) (3) (4) MIN TYP MAX 80 1 TYP MAX MIN 1.5 TYP MAX 7.5 9 10.5 60 1.7 1.7 7.5 9 10.5 Bit clock and Frame clock jitter has been included in the Set-up and hold timing. The LVDS timing depends on the state of the internal PLL. Use Table 4 to configure the PLL when decimation by 4 is enabled For any given ADC input clock frequency, TI recommends to use the highest PLL state to get best set-up time. The timing numbers are specified under this condition. Values below correspond to tdelay, not tPROG 8.14 LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 8 Filter Enabled See (1) (2) (3) ADC CLK Frequency (MSPS) Set-up Time (tsu), ns Hold Time (tH), ns tPROG = (5 / 7) × T + tdelay, ns (4) Fs = 1 / T Data Valid to ZeroCrossing of LCLKP (both edges) Zero-Crossing of LCLKP to Data Becoming Invalid (both edges) tPROG = delay from Input clock zero-cross rising edge to frame clock zero cross (rising edge) MIN 80 (1) (2) (3) (4) 16 2.9 TYP MAX MIN TYP 3.2 MAX MIN TYP MAX 7.5 9 10.5 Bit clock and Frame clock jitter has been included in the Set-up and hold timing. The LVDS timing depends on the state of the internal PLL. Use Table 5 to configure the PLL when decimation by 8 is enabled For any given ADC input clock frequency, TI recommends using the highest PLL state to get best set-up time. The timing numbers are specified under this condition. Values below correspond to tdelay, not tPROG Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 POWER SUPPLY AVDD, LVDD t1 RESET t2 t3 SEN (1) A high-going pulse on RESET pin is required in serial interface mode in case of initialization through hardware reset. Tie RESET permanently HIGH for parallel interface operation. (2) SEN refers to the CSZ pin. Figure 1. Reset Timing Diagram OUTP Logic Logic 0 0 VODL = -350 mV* Logic 0 VODH = +350 mV* OUTM VOCM GND GND *With external 100-W termination Figure 2. LVDS Output Voltage Levels Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 17 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Input Signal Sample N Sample N+td+1 Sample N+td ta ta td clock cycles latency Input Clock CLKIN Freq = fCLKIN Frame Clock ACLK Freq = fCLKIN T tPROG Bit Clock LCLK Freq = 7 x fCLKIN Output Data CHnOUT Data rate = 14 x fCLKIN D0 D1 (D12) (D13) D13 (D0) D12 (D1) D11 (D2) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D6 (D7) D5 (D8) D4 (D9) SAMPLE N-td D13 (D0) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D13 (D0) D12 (D1) D11 (D2) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D6 (D7) D5 (D8) D4 (D9) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D13 (D0) SAMPLE N-1 D12 (D1) D11 (D2) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D6 (D7) D5 (D8) D4 (D9) D0 D1 D3 D2 (D10) (D11) (D12) (D13) D11 (D0) D10 (D1) SAMPLE N Data bit in MSB First mode Data bit in LSB First mode Figure 3. 14-Bit 1-Wire LVDS Timing Diagram 18 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Input Signal Sample N ta td clock cycles latency Input Clock CLKIN Freq = fCLKIN Frame Clock ACLK Freq = fCLKIN Bit Clock LCLK Freq = 7 x fCLKIN Output Data CHnOUT Data rate = 14 x fCLKIN D0 D1 (D12) (D13) D13 (D0) D12 (D1) D11 (D2) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D6 (D7) D5 (D8) D4 (D9) D3 D2 D1 D0 (D10) (D11) (D12) (D13) SAMPLE N-td D13 (D0) Data bit in MSB First mode Data bit in LSB First mode Figure 4. Enlarged 1-Wire LVDS Timing Diagram (14 bit) Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 19 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Sample N-1 Input Signal Sample N Sample N+td ta ta Sample N+td+1 td cycles latency Input Clock CLKIN Freq = fCLKIN Frame Clock FCLK Freq = fCLKIN/2 T tPROP Bit Clock DCLK Freq = 3.5 x fCLKIN Output Data CHnOUT B Data rate = 7 x fCLKIN Output Data CHnOUT A Data rate = 7 x fCLKIN D7 (D6) D13 (D0) D12 (D1) D11 (D2) D1 D0 (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D8 (D5) D13 (D0) D7 (D6) D13 (D0) D12 (D1) D11 (D2) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D13 (D0) D12 (D1) D11 (D2) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D13 (D0) D12 (D1) D11 (D2) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D10 (D3) D9 (D4) D8 (D5) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D13 (D0) D12 (D1) D11 (D2) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D7 (D6) D13 (D0) D12 (D1) D11 (D2) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D13 (D0) D12 (D1) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D6 (D7) D5 (D8) D10 (D3) D9 (D4) D8 (D5) Data bit in MSB First mode SAMPLE N-td SAMPLE N-1 SAMPLE N SAMPLE N+1 Data bit in LSB First mode Figure 5. 14-Bit 2-Wire LVDS Timing Diagram 20 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Sample N-1 Input Signal Sample N ta Input Clock CLKIN Freq = fCLKIN Frame Clock FCLK Freq = fCLKIN/2 Bit Clock DCLK Freq = 3.5 x fCLKIN Output Data CHnOUT B Data rate = 7 x fCLKIN Output Data CHnOUT A Data rate = 7 x fCLKIN D7 (D6) D13 (D0) D12 (D1) D11 (D2) D1 D0 (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D8 (D5) D13 (D0) D7 (D6) D13 (D0) D12 (D1) D11 (D2) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D10 (D3) D9 (D4) D8 (D5) D10 (D3) D9 (D4) D8 (D5) D7 (D6) D3 D2 D1 D0 (D10) (D11) (D12) (D13) Data bit in MSB First mode SAMPLE N-td Data bit in LSB First mode Figure 6. Enlarged 2-Wire LVDS Timing Diagram (14 bit) Figure 7. Definition of Setup and Hold Times tSU = min(tSU1, tSU2); tH = min(tH1, tH2) Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 21 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 8.15 Typical Characteristics Typical values are at 25°C, AVDD = 1.8 V, LVDD = 1.8 V, 50% clock duty cycle, –1-dBFS differential analog input, 14 Bit/ 80 MSPS, ADC is configured in the internal reference mode, unless otherwise noted. 0 0 SNR = 76.1 dBFS SINAD = 75.7 dBFS SFDR = 87 dBc THD =84.7 dBc −10 −30 −30 −40 −40 −50 −50 −60 −70 −80 −60 −70 −80 −90 −90 −100 −100 −110 −110 −120 −120 −130 −140 −130 10 20 Frequency (MHz) 30 −140 40 Figure 8. FFT for 5-MHz Input Signal, Sample Rate = 80 MSPS −30 −40 −50 −50 Amplitude (dB) Amplitude (dB) −20 −40 −60 −70 −80 −70 −80 −90 −100 −100 −110 −110 −120 −120 −130 −130 10 20 Frequency (MHz) 30 −140 40 Figure 10. FFT for 65-MHz Input Signal, Sample Rate = 80 MSPS 10 Frequency (MHz) 15 20 0 SNR = 76.5 dBFS SINAD = 76.5 dBFS SFDR = 88.4 dBc THD = 87 dBc fIN1 = 8 MHz fIN2 = 10 MHz Each Tone at −7dBFS Amplitude Two Tone IMD = −91.4 dBFS −10 −20 −30 −30 −40 −40 −50 −50 Amplitude (dB) Amplitude (dB) 5 Figure 11. FFT for 5-MHz Input Signal, Sample Rate = 40 MSPS 0 −60 −70 −80 −60 −70 −80 −90 −90 −100 −100 −110 −110 −120 −120 −130 −130 5 10 Frequency (MHz) 15 20 −140 Figure 12. FFT for 15-MHz Input Signal, Sample Rate = 40 MSPS 22 40 −60 −90 −140 30 SNR = 76.5 dBFS SINAD = 76.5 dBFS SFDR = 90.23 dBc THD = 87 dBc −10 −30 −20 20 Frequency (MHz) 0 SNR = 70.7 dBFS SINAD =69.5 dBFS SFDR = 74.9 dBc THD =74.55 dBc −20 −10 10 Figure 9. FFT for 15-MHz Input Signal, Sample Rate = 80 MSPS 0 −10 −140 SNR = 75.5 dBFS SINAD = 74.4 dBFS SFDR = 80.3 dBc THD =79.7 dBc −20 Amplitude (dB) Amplitude (dB) −20 −10 Submit Documentation Feedback 10 20 Frequency (MHz) 30 40 Figure 13. Two-Tone Intermodulation Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Typical Characteristics (continued) Typical values are at 25°C, AVDD = 1.8 V, LVDD = 1.8 V, 50% clock duty cycle, –1-dBFS differential analog input, 14 Bit/ 80 MSPS, ADC is configured in the internal reference mode, unless otherwise noted. 77 86 76 84 82 75 SFDR (dBc) SNR (dBFS) 80 74 73 78 76 72 74 71 5 15 25 35 45 55 65 Input Signal frequency (MHz) 75 70 85 Figure 14. Signal-To-Noise Ratio vs Input Signal Frequency 5 15 25 35 45 55 65 Input Signal frequency (MHz) 90 Input frequency = 10 MHz Input frequency = 70 MHz Input frequency = 10 MHz Input frequency = 70 MHz 76 86 72 82 SFDR (dBc) SNR (dBFS) 85 Figure 15. Spurious-Free Dynamic Range vs Input Signal Frequency 80 68 64 60 75 78 74 0 1 2 3 4 5 6 7 8 Digital gain (dB) 9 10 11 70 12 0 1 2 3 4 5 6 7 8 Digital gain (dB) 9 10 11 12 G001 G001 Figure 17. SFDR vs Digital Gain 80 110 79.5 100 79 90 78.5 80 78 70 77.5 60 77 50 76.5 40 76 30 75.5 20 SNR SFDR(dBc) SFDR(dBFS) 10 0 −96 −86 −76 −66 −56 −46 −36 −26 Input amplitude (dBFS) −16 −6 0 78 88 SFDR SNR 75 SFDR (dBc) 120 SNR (dBFS) SFDR (dBFS,dBc) Figure 16. SNR vs Digital Gain 87 77 86 76 85 75 84 74 83 73 SNR (dBFS) 70 72 74.5 74 Figure 18. Performance vs Input Amplitude 82 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Input Clock Amplitude, differential (Vp−p) 2.2 72 2.4 Figure 19. Performance vs Clock Input Amplitudes Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 23 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Typical Characteristics (continued) Typical values are at 25°C, AVDD = 1.8 V, LVDD = 1.8 V, 50% clock duty cycle, –1-dBFS differential analog input, 14 Bit/ 80 MSPS, ADC is configured in the internal reference mode, unless otherwise noted. 77 86 Fin = 5 MHz 74.5 83.5 77 87 76.5 86 76 85 75.5 84 75 83 74.5 82 74 81 73.5 SNR (dBFS) SFDR (dBc) 75 84 SNR (dBFS) 75.5 84.5 SFDR (dBc) 77.5 88 76 85 74 83 73.5 82.5 35 40 45 50 55 Input Clock Duty Cycle (%) 60 65 73 80 0.80 Figure 20. Performance vs Input Clock Duty CyclePerformance vs Input Clock Duty Cycle 0.85 0.90 0.95 1.00 1.05 Analog Input Common−mode voltage (V) 73 1.10 Figure 21. Performance vs Input VCM 77.0 88 AVDD=1.65V AVDD=1.7V AVDD=1.8V AVDD=1.9V AVDD=1.95V 76.5 AVDD=1.65V AVDD=1.7V AVDD=1.8V AVDD=1.9V AVDD=1.95V 87 86 85 76.0 84 SFDR (dBc) SNR (dBFS) SFDR SNR 89 76.5 85.5 82 78 90 SFDR SNR 75.5 83 82 75.0 81 80 74.5 79 74.0 −40 −20 0 20 40 Temperature (°C) 60 78 −40 80 Figure 22. Signal-To-Noise Ratio vs Temperature −20 0 20 40 Temperature (°C) 60 80 Figure 23. Spurious-Free Dynamic Range vs Temperature 100 −110 Far Channel Near Channel 95 Phase Noise (dBc/Hz) −120 Crosstalk (dB) 90 85 80 10 20 30 40 50 60 Frequency of Aggressor Channel (MHz) 70 Figure 24. Crosstalk vs Frequency 24 −140 −150 75 70 −130 −160 0.01 0.1 1 Frequency Offset (kHz) 10 100 Figure 25. Phase Noise for 5-MHz Input Signal, Sample Rate = 80 MSPS Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Typical Characteristics (continued) Typical values are at 25°C, AVDD = 1.8 V, LVDD = 1.8 V, 50% clock duty cycle, –1-dBFS differential analog input, 14 Bit/ 80 MSPS, ADC is configured in the internal reference mode, unless otherwise noted. 0.3 0.8 0.7 0.6 0.2 0.5 0.4 0.3 0.1 DNL (LSB) INL (LSB) 0.2 0.1 0.0 −0.1 0.0 −0.2 −0.1 −0.3 −0.4 −0.5 −0.2 −0.6 −0.7 −0.8 900 3900 6900 9900 Output_codes (dB) 12900 −0.3 900 15900 Figure 26. Integral Non-Linearity 3900 6900 9900 Output_codes (LSB) 12900 15400 Figure 27. Differential Non-Linearity 80 With 50mVpp signal superimposed on input common−mode Fin = 3 MHz 45.5 70 CMRR (dB) 31.53 16.18 0.03 50 40 5.55 0.1 60 0.11 30 Figure 28. Histogram of Output Code With Analog Inputs Shorted (RMS Noise = 96.4 uV) a note "RMS Noise = 96.4 uV" to Figure 28 20 30 40 50 Frequency of CMRR signal (MHz) 60 70 20 With 50mVpp signal superimposed on AVDD supply PSMR: 3MHz input signal applied PSRR: No input signal applied PSMR PSRR Low Pass High pass 10 0 −30 Normalized Amplitude (dB) Power Supply Rejection (dB) 10 Figure 29. Common Mode Rejection Ratio vs Frequency −10 −20 0 −40 −50 −60 −10 −20 −30 −40 −50 −60 −70 −70 −80 0.01 0.1 1 10 Frequency of signal on supply (MHz) 70 Figure 30. Power-Supply Rejection Ratio vs Frequency −80 0.0 0.1 0.2 0.3 0.4 Normalized Frequency (fin/fs) 0.5 Figure 31. Filter Response, Decimate by 2 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 25 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Typical Characteristics (continued) Typical values are at 25°C, AVDD = 1.8 V, LVDD = 1.8 V, 50% clock duty cycle, –1-dBFS differential analog input, 14 Bit/ 80 MSPS, ADC is configured in the internal reference mode, unless otherwise noted. 40 0 Low Pass Band−Pass1 Band−Pass2 High Pass 30 20 SNR = 78.2 dBFS SINAD = 78.2 dBFS Decimate by 2 Filter Enabled −10 −20 −30 −40 0 −50 Amplitude (dB) Normalized Amplitude (dB) 10 −10 −20 −30 −60 −70 −80 −90 −40 −100 −50 −110 −60 −120 −70 −130 −80 0.0 0.1 0.2 0.3 Normalized frequency (fin/fs) 0.4 −140 0.5 Figure 32. Filter Response, Decimate by 4 5 10 Frequency (MHz) 15 20 Figure 33. FFT for 5-MHz Input Signal, Sample Rate = 80 MSPS with Decimation Filter = 2 0 3 SNR = 77.9 dBFS SINAD = 77.9 dBFS SFDR = 93.13 dBc THD = −96 dBc 2 Channels averaged −10 −20 −30 0 −3 −6 −9 Normalized Amplitude (dB) −40 −50 Amplitude (dB) 0 −60 −70 −80 −90 −100 −12 −15 −18 −21 −24 K=2 K=3 K=4 K=5 K=6 K=7 K=8 K=9 K=10 −27 −30 −33 −110 −36 −120 −39 −130 −140 −42 0 5 10 15 20 25 Frequency (MHz) 30 35 −45 0.02 40 Figure 34. FFT for 5-MHz Input Signal, Sample Rate = 80 MSPS by Averaging 2 Channels 0 −5 HPF_DISABLED HPF_ENABLED −20 −15 −30 −25 −40 −35 −50 −45 Amplitude (dB) Amplitude (dB) 10 15 Figure 35. Digital High-Pass Filter Response 0 −10 0.1 1 Input Signal Frequency (MHz) −60 −70 −80 −90 −55 −65 −75 −100 −85 −110 −95 −120 −105 −130 −115 −140 −150 0 0.5 1 1.5 2 2.5 3 3.5 Input Signal Frequency (MHz) 4 4.5 5 Figure 36. FFT with HPF Enabled and Disabled, No Signal 26 −125 0 5 10 15 20 25 Frequency (MHz) 30 35 40 Figure 37. FFT (Full-Band) for 5-MHz Input Signal, Sample Rate = 80 MSPS with Low Frequency Noise Suppression Enabled Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Typical Characteristics (continued) Typical values are at 25°C, AVDD = 1.8 V, LVDD = 1.8 V, 50% clock duty cycle, –1-dBFS differential analog input, 14 Bit/ 80 MSPS, ADC is configured in the internal reference mode, unless otherwise noted. 0 0 LF noise suppression enabled LF noise suppression disabled −20 −20 −30 −30 −40 −40 −50 −50 −60 −70 −80 −60 −70 −80 −90 −90 −100 −100 −110 −110 −120 −120 −130 −130 −140 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Frequency (MHz) 0.8 0.9 LF noise suppression enabled LF noise suppression disabled −10 Amplitude (dB) Amplitude (dB) −10 −140 1 Figure 38. FFT (0 to 1 MHz) for 5-MHz Input Signal, Sample Rate = 80 MSPS with Low Frequency Noise Suppression Enabled 39 39.1 39.2 39.3 39.4 39.5 39.6 39.7 39.8 39.9 Frequency (MHz) 40 Figure 39. FFT (39 MHz to 40 MHz) for 5-MHz Input Signal, Sample Rate = 80 MSPS with Low Frequency Noise Suppression Enabled 450 350 2−wire 1−wire 1−wire Decimate by 2 325 400 300 Digital Power (mW) Analog Power (mW) 275 350 300 250 250 225 200 175 150 125 200 100 75 150 10 20 30 40 50 60 Sampling Frequency (MSPS) 70 Figure 40. Power Consumption on Analog Supply 190 220 170 200 150 180 160 140 110 90 70 100 50 10 20 30 40 50 60 Sampling Frequency (MSPS) 70 30 80 Figure 42. Supply Current on Analog Supply 2−wire 1−wire 1−wire Decimate by 2 130 120 80 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Sampling Frequency (MSPS) Figure 41. Power Consumption on Digital Supply 240 Digital Current (mA) Analog Current (mA) 50 80 10 20 30 40 50 60 Sampling Frequency (MSPS) 70 80 Figure 43. Supply Current on Digital Supply Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 27 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 9 Detailed Description 9.1 Overview The ADS5294 is an octal-channel, 14-bit, high-speed ADC with a sample rate of up to 80 MSPS that runs off a single 1.8-V supply. All eight channels of the ADS5294 simultaneously sample the respective analog inputs at the rising edge of the input clock. The sampled signal is sequentially converted by a series of small resolution stages, with the outputs combined in a digital correction logic block. At every clock, edge the sample propagates through the pipeline resulting in a data latency of 11 clock cycles. The 14 data bits of each channel are serialized and sent out in either 1-wire mode (one pair of LVDS pins are used) or 2-wire mode (two pairs of LVDS pins are used), depending on the LVDS output rate. When the data is output in the 2-wire mode, it reduces the serial data rate of the outputs, especially at higher sampling rates. Lowcost FPGAs are used to capture 80 MSPS / 14-bit data. Alternately, at lower sample rates, the 14-bit data is output as a single data stream over one pair of LVDS pins (1-wire mode). The device outputs a bit clock at 7x and frame clock at 1x the sample frequency in the 14-bit mode. This 14-bit ADC achieves approximately 76-dBFS SNR at 80 MSPS. Its output resolution can be configured as 12-bit and 10-bit, if necessary. When the output resolution of the ADS5294 is 12-bit and 10-bit, SNR of 72 dBFS and 61 dBFS (respectively) is achieved. 28 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 9.2 Functional Block Diagram Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 29 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 9.3 Feature Description 9.3.1 Analog Input The analog inputs consist of a switched-capacitor-based differential sample and hold architecture. This differential topology results in good AC performance even for high input frequencies at high sampling rates. The INP and INM pins are internally biased around a common-mode voltage of Vcm (0.95 V). For a full-scale differential input, each input pin (INP and INM) must swing symmetrically between Vcm + 0.5 V and Vcm – 0.5 V, resulting in a 2 VPP differential input swing. Figure 44 shows the equivalent circuit of the input sampling circuit. (1) SZ MOSFETs' open ends connect to common mode potential, while they don't impact the inputs' loading. Users may treat the open ends as high impedance nodes. Figure 44. Analog Input Circuit Model 9.3.2 Input Clock Figure 45 shows the clock equivalent circuit of the ADS5294. The ADS5294 is configured by default to operate with a single-ended input clock. CLKP is driven by a CMOS clock and CLKM is tied to GND. The device automatically detects a single-ended or differential clock. If CLKM is grounded, the device treats clock as a single-ended clock. Operating with a low-jitter differential clock usually gives better SNR performance, especially at input frequencies greater than 30 MHz. 30 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Feature Description (continued) Clock buffer Lpkg ~ 2 nH 5Ω CLKP Ceq Cbond ~ 0.5 pF Resr ~ 200 Ω 6 pF VCM 6 pF Lpkg ~ 2 nH Ceq 5 kΩ 5 kΩ 5Ω CLKM Cbond ~ 0.5 pF Resr ~ 200 Ω Ceq is approximately 1 to 3 pF, equivalent input capacitance of clock buffer. Figure 45. Equivalent Circut of the Input Clock Circuit Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 31 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Feature Description (continued) 9.3.3 Digital Highpass IIR Filter DC offset is often observed at ADC input signals. For example, in ultrasound applications, the DC offset from variable-gain amplifier (VGA) varies at different gains. Such a variable offset can introduce artifacts in ultrasound images especially in Doppler modes. Analog filter between ADC and VGA can be used with added noise and power. Digital filter achieves the same performance as analog filters and has more flexibility in fine tuning multiple characteristics. ADS5294 includes optional first-order digital high-pass (HP) IIR filter. Figure 46 shows the device block diagram and transfer function. y(n) = 2 k k 2 +1 [x(n) - x(n - 1)+y(n - 1)] (1) Figure 46. HP Filter Block Diagram Figure 47 shows the characteristics at k=2 to 10. 3 0 −3 −6 Normalized Amplitude (dB) −9 −12 −15 −18 −21 −24 K=2 K=3 K=4 K=5 K=6 K=7 K=8 K=9 K=10 −27 −30 −33 −36 −39 −42 −45 0.02 0.1 1 Input Signal Frequency (MHz) 10 15 Figure 47. HP Filter Amplitude Response at K = 2 to 10 32 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Feature Description (continued) 9.3.4 Decimation Filter ADS5294 includes an option to decimate the ADC output data using filters. Once the decimation is enabled, the decimation rate, frequency band of the filter can be programmed. In addition, the user can select either the predefined or custom coefficients. Table 1. Digital Filters (1) TYPE OF FILTER DATA _RATE FILTERn _RATE FILTERn _COEFF_SET ODD_TAP USE _FILTER _CHn EN_CUSTOM _FILT Built-in low-pass odd-tap filter (pass band = 0 to fS / 4) 01 000 000 1 1 0 Built-in high-pass odd-tap filter (pass band = fS / 4 to fS /2) 01 000 001 1 1 0 Built-in low-pass even-tap filter (pass band = 0 to fS / 8) 10 001 010 0 1 0 Built-in first band pass even tap filter (pass band = fS / 8 to fS / 4) 10 001 011 0 1 0 Built-in second band pass even tap filter (pass band = fS / 4 to 3 fS / 8) 10 001 100 0 1 0 Built-in high pass odd tap filter (pass band = 3 fS / 8 to fS / 2) 10 001 101 1 1 0 Decimate by 2 Custom filter (user-programmable coefficients) 01 000 000 0 and 1 1 1 Decimate by 4 Custom filter (user-programmable coefficients) 10 001 000 0 and 1 1 1 Decimate by 8 Custom filter (user-programmable coefficients) 11 100 000 0 and 1 1 1 Bypass decimation Custom filter (user-programmable coefficients) 00 011 000 0 and 1 1 1 DECIMATION Decimate by 2 Decimate by 4 (1) EN_CUSTOM_FILT is the D15 of register 5A (Hex) to B9 (Hex). 9.3.5 Decimation Filter Equation In the default setting, the decimation filter is implemented as a 24-tap FIR filter with symmetrical coefficients (each coefficient is 12-bit signed). By setting the register bit ODD_TAPn = 1, a 23-tap FIR is implemented 9.3.5.1 Pre-defined Coefficients The built-in filters (lowpass, highpass, and bandpass) use pre-defined coefficients. The frequency responses of the build-in decimation filters with different decimation factors are shown in Figure 48. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 33 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 40 20 Low Pass High pass 10 Low Pass Band−Pass1 Band−Pass2 High Pass 30 20 0 Normalized Amplitude (dB) Normalized Amplitude (dB) 10 −10 −20 −30 −40 −50 0 −10 −20 −30 −40 −50 −60 −60 −70 −80 0.0 −70 0.1 0.2 0.3 0.4 Normalized Frequency (fin/fs) 0.5 −80 0.0 Figure 48. Decimation Filter Responses (Decimate by 2) 34 Submit Documentation Feedback 0.1 0.2 0.3 Normalized frequency (fin/fs) 0.4 0.5 Figure 49. Decimation Filter Responses (Decimate by 4) Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 9.3.5.2 Custom Filter Coefficients The filter coefficients are also programmed, or customized, by the user. For custom coefficients, set the register bit and load the coefficients (h0 to h11) in registers 0x5A to 0xB9, using the serial interface as: Register content = real coefficient value × 211, 12-bit signed representation of real coefficient. 9.3.6 PLL Operation Versus LVDS Timing The ADS5294 uses a PLL that automatically changes configuration to one of four states depending on the sampling clock frequency. The clock frequency detection is automatic and each time the sampling frequency crosses a threshold, the PLL changes configuration to a new state. The PLL remains in the new state for a range of clock frequencies. To prevent unwanted toggling of PLL state around a threshold, the circuit has an built-in hysteresis. The ADS5294 has three thresholds over the sampling clock frequency range from 10 MHz to 80 MHz and can be in one of four states as shown by Figure 50. Figure 50. PLL States Versus ADC Fs Each threshold shifts by a small amount across temperature. On power up, depending on the clock frequency, the PLL settles in one of four states. Later, as the system warms up, the PLL changes state once due to the shift in the threshold across temperature. 9.3.6.1 Effect on Output Timings The PLL state change has an effect on the output LVDS timings. In some settings, the set-up time decreases by 100 ps typically with a corresponding increase in the hold time. In applications where a timing calibration occurs at the system level once after power-up, this subsequent change of the PLL state is undesirable. The ADS5294 has register options to disable the automatic switch of the PLL state based on frequency detected. To prevent this variation in output timing, disable the PLL from switching states. In addition to disabling the auto-switching, setting the PLL to the correct state is also required, depending on the sample clock frequency used in the system. The following sequence of register writes must be followed exactly: • • Step 1: Enable test-mode access by writing register data = 0x0010 in address 0x01 (for example: enable the access to registers with address higher than 0xF0). Step 2: Configure the PLL to the correct state depending on the clock frequency of operation and the decimation factor, as per the following tables. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 35 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com NOTE For certain sampling frequencies, there are two PLL states possible, both of which are stable. In such cases, the higher PLL state results in a better set-up time compared to a lower PLL state. For example, at 80 MSPS, with decimation by 2 enabled, the PLL may be in states 3 or 4. However, the set-up time value specified in LVDS Timing at Different Sampling Frequencies — 1-Wire Interface, 14x-Serialization, Decimation by 2 Filter Enabled (0.43 ns minimum) is in PLL state 4. In state 3, the set-up time is reduced further by 100 ps typically, with a corresponding increase in the hold time. Table 2. PLL Configuration When Decimation is Disabled ADC Fs (MSPS) REGISTER ADDRESS REGISTER DATA Fs ≤ 12 Disable PLL auto state switch and put PLL in state 1 FUNCTION 0xD1 0x0040 9 ≤ Fs ≤ 24 Disable PLL auto state switch and put PLL in state 2 0xD1 0x00C0 18 ≤ Fs ≤ 42 Disable PLL auto state switch and put PLL in state 3 0xD1 0x0140 Fs ≥ 28 Disable PLL auto state switch and put PLL in state 4 0xD1 0x0240 Table 3. PLL Configuration When Decimation by 2 is Used ADC Fs 36 REGISTER ADDRESS REGISTER DATA Fs ≤ 24 Disable PLL auto state switch and put PLL in state 1 FUNCTION 0xD1 0x0040 18 ≤ Fs ≤ 48 Disable PLL auto state switch and put PLL in state 2 0xD1 0x00C0 36 ≤ Fs ≤ 80 Disable PLL auto state switch and put PLL in state 3 0xD1 0x0140 Fs ≥ 56 Disable PLL auto state switch and put PLL in state 4 0xD1 0x0240 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Table 4. PLL Configuration When Decimation by 4 is Used ADC Fs REGISTER ADDRESS REGISTER DATA Fs ≤ 48 Disable PLL auto state switch and put PLL in state 1 FUNCTION 0xD1 0x0040 36 ≤ Fs ≤ 80 Disable PLL auto state switch and put PLL in state 2 0xD1 0x00C0 Fs ≥ 72 Disable PLL auto state switch and put PLL in state 3 0xD1 0x0140 Table 5. PLL Configuration When Decimation by 8 is Used ADC Fs REGISTER ADDRESS REGISTER DATA Fs ≤ 80 Disable PLL auto state switch and put PLL in state 1 FUNCTION 0xD1 0x0040 72 ≤ Fs ≤ 80 Disable PLL auto state switch and put PLL in state 2 0xD1 0x00C0 9.4 Device Functional Modes ADC Output Resolution and LVDS Serialization Rate Modes: The LVDS serialization rate can be programmed as 10, 12, 14, or 16 bits by the EN_BIT_SER register bit. Output Data Rate Modes: The density of output data payload can be set to 1X or 2X mode by using the EN_SDR register bit. The maximum data rate (in bits per sec) of the LVDS interface is limited. In addtion, the LVDS data can be distributed by one pair LVDS data lane or two pairs of LVDS data lanes. Please see the description of Registers 0x50 to 0x55 in the Programmable Mapping Between Input Channels and Output Pins section. When the decimation feature is used, the LVDS output rate can be reduced to 1/2, 1/4, and 1/8 of ADC sampling rate as Output Data Rate Control shows. The flexible output data rate modes give users a wide selection of different speed FPGAs. Power Modes: The device can be configured via SPI or pin settings to a complete power-down mode and via pin settings to a partial power-down (standby mode). During these two modes (complete and partial power-down), different internal functions stay powered up, resulting in different power consumption and wake-up times. In the partial power-down mode, all LVDS data lanes are powered down. The bit clock and frame clock lanes remain enabled to save time to sync again on the receiver side. However, in the complete power-down mode all lanes are powered down and thus this mode requires more time to wake-up because the bit clock and frame clock lanes must sync again with the receiver device. LVDS Test Pattern Mode: The ADC data coming out of the LVDS outputs can be replaced by different kinds of test patterns. Note that the test patterns replace the data streaming out of the ADCs. The different test patterns are described in LVDS Test Patterns. 9.5 Programming 9.5.1 Serial Interface ADS5294 has a set of internal registers that can be accessed by the serial interface formed by pins CSZ (Serial interface Enable – Active Low), SCLK (Serial Interface Clock), and SDATA (Serial Interface Data). When CSZ is low, • Serial shift of bits into the device is enabled • Serial data (SDATA) is latched at every rising edge of SCLK • SDATA is loaded into the register at every 24th SCLK rising edge. If the word length exceeds a multiple of 24 bits, the excess bits are ignored. Data can be loaded in multiples of 24-bit words within a single active CSZ pulse. The first eight bits form the register address and the remaining 16 bits form the register data. The interface works with SCLK frequencies from 15 MHz down to very low speeds (a few Hertz) and also with non-50% SCLK duty cycle. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 37 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Programming (continued) 9.5.1.1 Register Initialization After power-up, initialize the internal registers to the respective default values. Initialization occurs in one of two ways: 1. Through a hardware reset, by applying a high pulse on the RESET pin. 2. Through a software reset: using the serial interface, set the RST bit high. Setting this bit initializes the internal registers to the respective default values and then self-resets the bit low. In this case, the RESET pin stays low (inactive). REGISTER DATA REGISTER ADDRESS SDATA A7 A6 A5 A4 A3 A2 A1 A0 D15 D14 D13 D12 tDSU D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 tDH SCLK tSLOADH tSCLK CSZ tSLOADS RESET Figure 51. Serial Interface Timing Please refer to Serial Interface Timing Requirements for more details. 9.5.1.2 Serial Register Readout The device includes a mode where the contents of the internal registers can be read back on the SDOUT pin. This mode is useful as a diagnostic check to verify the serial interface communication between the external controller and the ADC. By default, after power up and device reset, the SDOUT pin is in the high-impedance state. When the readout mode is enabled using the register bit , SDOUT outputs the contents of the selected register serially, described as follows. • Set register bit = 1 to put the device in serial readout mode. This setting disables any further writes into the internal registers, EXCEPT the register at address 1. – Note that the bit itself is also located in register 1. The device can exit readout mode by writing to 0. Only the contents of register at address 1 cannot be read in the register readout mode. • Initiate a serial interface cycle specifying the address of the register (A7–A0) whose content is to be read. • The device serially outputs the contents (D15–D0) of the selected register on the SDOUT pin. • The external controller can latch the contents at the rising edge of SCLK. • To exit the serial readout mode, reset register bit = 0, which enables writes into all registers of the device. At this point, the SDOUT pin enters the high-impedance state. 38 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Programming (continued) A) Enable Serial Readout ( = 1) REGISTER DATA (D15:D0) = 0x0001 REGISTER ADDRESS (A7:A0) = 0x01 SDATA 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 SCLK CSZ Pin SDOUT Becomes Active and Forces Low Pin SDOUT is tri-stated SDOUT B) Read Contents of Register 0x0F. This Register has been Initialized with 0x0200 (The Device was earlier put in global power down) REGISTER DATA (D15:D0) = XXXX (don’t care) REGISTER ADDRESS (A7:A0) = 0x0F SDATA A7 A6 A5 A4 A3 A2 0 0 0 0 0 0 A1 A0 0 0 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 0 0 0 0 0 0 0 0 0 SCLK CSZ SDOUT 0 0 0 0 0 0 1 SDOUT Output Contents of Register 0x0F in the same cycle, MSB first Figure 52. Serial Readout Timing 9.5.1.3 Default States After Reset • Device is in normal operation mode with 14-bit ADC enabled for all channels • Output interface is 1-wire, 14×-serialization with 7×-bit clock and 1×-frame clock frequency • Serial readout is disabled • PDN pin is configured as global power-down pin • Digital gain is set to 0 dB • Digital modes such as LFNS and digital filters are disabled Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 39 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 9.6 Register Maps Table 6. Summary of Functions Supported by Serial Interface ADDR. (HEX) D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 00 D0 (1) (2) (3) (4) NAME X RST X EN_READOUT 01 X 02 0A EN_HIGH_ADDRS X X X X EN_SYNC X X X X X DESCRIPTION 1: Self-clearing software RESET; . After reset, this bit is set to 0 0: Normal operation. 1: READOUT of registers mode;0: Normal operation 0 – Disable access to register at address 0xF0 1 – Enable access to register at address 0xF0 1:Enable SYNC feature to synchronize the test patterns; 0: Normal operation, SYNC feature is disabled for the test patterns. Note: this bit needs to be set as 1 when software or hardware SYNC feature is used. see Reg.0x25[8] and 0x25[15] X X X X X X X X RAMP_PAT_RESET_VAL X X X X X X X X PDN_CH 1:Channel-specific ADC power-down mode; 0: Normal operation PDN_PARTIAL 1:Partial power-down mode - fast recovery from power-down; 0: Normal operation PDN_COMPLETE 1:Register mode for complete power-down - slower recovery; 0: Normal operation X Ramp pattern reset value 0F X X 14 X X X X X X X X X PDN_PIN_CFG 1:Configures PD pin for partial power-down mode; 0:Configures PD pin for complete power-down mode LFNS_CH 1: Channel-specific low-frequency noise suppression mode enable; 0: LFNS disabled EN_FRAME_PAT 1: Enables output frame clock to be programmed through a pattern; 0: Normal operation on frame clock 1C 23 X X X X X X X X X X X X X X X X ADCLKOUT 14-bit pattern for frame clock on ADCLKP and ADCLKN pins X X X X X X X X X X X X X X PRBS_SEED PRBS pattern starting seed value lower 16 bits X X X X X X X X INVERT_CH 24 X (1) (2) (3) (4) 40 X X X X X X PRBS_SEED 1: Swaps the polarity of the analog input pins electrically; 0: Normal configuration PRBS seed starting value upper 7 bits The unused bits in each register (identified as blank table cells) must be programmed as '0'. X = Register bit referenced by the corresponding name and description Bits marked as '0' should be forced to 0, and bits marked as '1' should be forced to 1 when the particular register is programmed. Multiple functions in a register can be programmed in a single write operation. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Register Maps (continued) Table 6. Summary of Functions Supported by Serial Interface ADDR. (HEX) D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 (1)(2)(3)(4) (continued) NAME DESCRIPTION 1: Enables a repeating full-scale ramp pattern on the outputs; 0: Normal operation X 0 0 EN_RAMP 0 X 0 DUALCUSTOM_PAT 0 0 X SINGLE_CUSTOM_PAT 1: Enables mode wherein output is a constant specified code; 0: Normal operation BITS_CUSTOM1 2 MSBs for single custom pattern (and for the first code of the dual custom patterns) BITS_CUSTOM2 2 MSBs for second code of the dual custom patterns X X X X 25 X TP_SOFT_SYNC X PRBS_TP_EN X PRBS_MODE_2 X PRBS_SEED_FROM_REG X 1:Enables mode wherein output toggles between two defined codes; 0: Normal operation 1: Software sync bit for test patterns on all 8 CHs; 0: No sync. Note: in order to synchronize the digital filters using the SYNC pin, this bit must be set as 0. 1: PRBS test pattern enable bit; 0: PRBS test pattern disabled PRBS 9 bit LFSR (23bit LFSR is default) 1: Enable PRBS seed to be chosen from register 0x23 and 0x24; 0: Disabled TP_HARD_SYNC 1: Enable the external SYNC feature for syncing test patterns. 0: Inactive. Note: in order to synchronize the digital filters using the SYNC pin, this bit must be set as 0. 26 X X X X X X X X X X X X BITS_CUSTOM1 12 lower bits for single custom pattern (and for the first code of the dual custom pattern). 27 X X X X X X X X X X X X BITS_CUSTOM2 12 lower bits for second code of the dual custom pattern X EN_BITORDER X X BIT_WISE 28 1 X X X X X X X X EN_WORDWISE__BY_CH Enables the bit order output. 0 = byte-wise, 1 = word-wise or bit-wise Selects between byte-wise and bit-wise 1: bit-wise, odd bits come out on one wire and even bits come out on other wire. D15 must be set to '1' for the bit-wise mode. 0: byte-wise, upper bits on one wire and lower bits on other wire D15 must be set to '0' for the byte-wise mode. 1: Output format is one sample on one LVDS wire and next sample on other LVDS wire. 0: Data comes out in 2-wire mode with upper set of bits on one channel and lower set of bits on the other. Note: D15 must set to '1' for the word-wise mode. GLOBAL_EN_FILTER 1: Enables filter blocks - global control; 0: Inactive X EN_CHANNEL_AVG 1: Enables channel averaging mode; 0: Inactive X GAIN_CH1 Programmable gain - Channel 1 GAIN_CH2 Programmable gain - Channel 2 GAIN_CH3 Programmable gain - Channel 3 GAIN_CH4 Programmable gain - Channel 4 X 29 X X X X X X X 2A X X X X X X X X Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 41 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Register Maps (continued) Table 6. Summary of Functions Supported by Serial Interface ADDR. (HEX) D15 D14 D13 D12 X X X X D11 X D10 X D9 X D8 D7 D6 D5 D4 D3 D2 D1 D0 X (1)(2)(3)(4) (continued) NAME DESCRIPTION GAIN_CH5 Programmable gain - Channel 5 GAIN_CH6 Programmable gain - Channel 6 GAIN_CH7 Programmable gain - Channel 7 GAIN_CH8 Programmable gain - Channel 8 2B X X X X X X X X X X X X AVG_CTRL4 Averaging control for what comes out on LVDS output OUT4 AVG_CTRL3 Averaging control for what comes out on LVDS output OUT3 AVG_CTRL2 Averaging control for what comes out on LVDS output OUT2 AVG_CTRL1 Averaging control for what comes out on LVDS output OUT1 AVG_CTRL8 Averaging control for what comes out on LVDS output OUT8 AVG_CTRL7 Averaging control for what comes out on LVDS output OUT7 AVG_CTRL6 Averaging control for what comes out on LVDS output OUT6 AVG_CTRL5 Averaging control for what comes out on LVDS output OUT5 2C X X X X X X X X 2D X X X X X X X FILTER1_COEFF_SET X X X FILTER1_RATE X 2E ODD_TAP1 X X X X X X X X X X X 2F X X X X X X X X X X 30 X X X X 42 USE_FILTER2 Submit Documentation Feedback Select stored coefficient set for filter 2 Set decimation factor for filter 2 Use odd tap filter 2 1: Enables filter for channel 2; 0: Disables HPF_CORNER _CH2 HPF corner in values k from 2 to 10 HPF_EN_CH2 1: HPF filter enabled for the channel; 0: Disabled FILTER3_COEFF_SET Select stored coefficient set for filter 3 ODD_TAP3 X X 1: HPF filter enable for the channel; 0: Disables FILTER3_RATE X 1: Enables filter for channel 1; 0: Disables HPF_EN_CH1 ODD_TAP2 X Use odd tap filter 1 HPF corner in values k from 2 to 10 FILTER2_RATE X Set decimation factor for filter 1 HPF_CORNER _CH1 FILTER2_COEFF_SET X X USE_FILTER1 Select stored coefficient set for filter 1 USE_FILTER3 Set decimation factor for filter 3 Use odd tap filter 3 1: Enables filter for channel 3; 0: Disables HPF_CORNER _CH3 HPF corner in values k from 2 to 10 HPF_EN_CH3 1: HPF filter enabled for the channel; 0: Disabled Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Register Maps (continued) Table 6. Summary of Functions Supported by Serial Interface ADDR. (HEX) D15 D14 D13 D12 D11 D10 D9 D8 D7 X X X D6 D5 D4 D3 D2 D1 D0 X X FILTER4_RATE X 31 ODD_TAP4 X X X X X X X X X X X 32 X X X X X X X X X 33 X X X X FILTER5_COEFF_SET Select stored coefficient set for filter 5 USE_FILTER5 X X 1: HPF filter enabled for the channel; 0: Disabled FILTER_TYPE6 Select stored coefficient set for filter 6 USE_FILTER6 DECBY8_7 X X 34 FILTER_MODE7 X ODD_TAP7 X X X X X USE_FILTER7 HPF_CORNER _CH7 X HPF_EN_CH7 X X X FILTER_TYPE8 X DECBY8_8 X X FILTER_MODE8 X ODD_TAP8 35 X X X X X X 1: Enables filter for channel 5; 0: Disables HPF_EN_CH5 FILTER_TYPE7 X Use odd tap filter 5 HPF corner in values k from 2 to 10 HPF_EN_CH6 X Set decimation factor for filter 5 HPF_CORNER _CH5 HPF_CORNER _CH6 X 1: Enables filter for channel 4; 0: Disables 1: HPF filter enabled for the channel; 0: Disabled ODD_TAP6 X Use odd tap filter 4 HPF_EN_CH4 FILTER_MODE6 X Set decimation factor for filter 4 HPF corner in values k from 2 to 10 DECBY8_6 X DESCRIPTION Select stored coefficient set for filter 4 HPF_CORNER _CH4 ODD_TAP5 X X USE_FILTER4 FILTER5_RATE X (continued) NAME FILTER4_COEFF_SET X X (1)(2)(3)(4) USE_FILTER8 Enables decimate by 8 filter 6 Set decimation factor for filter 6 Use odd tap filter 6 Enables filter for channel 6 HPF corner in values k from 2 to 10 HPF filter enable for the channel Select stored coefficient set for filter 7 Enables decimate by 8 filter 7 Set decimation factor for filter 7 Use odd tap filter 7 Enables filter for channel 7 HPF corner in values k from 2 to 10 HPF filter enable for the channel Select stored coefficient set for filter 8 Enables decimate by 8 filter 8 Set decimation factor for filter 8 Use odd tap filter 8 1: Enables filter for channel 8; 0: Disables HPF_CORNER_CH8 HPF corner in values k from 2 to 10 HPF_EN_CH8 1: HPF filter enable for the channel; 0: Disables Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 43 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Register Maps (continued) Table 6. Summary of Functions Supported by Serial Interface ADDR. (HEX) D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 38 X (1)(2)(3)(4) D1 D0 NAME DESCRIPTION X X DATA_RATE Select output frame clock rate. Please see Output Data Rate Control. X EXT_REF_VCM 42 X (continued) X PHASE_DDR Drive external reference mode through: D15 = D3 = 1: the VCM pin; D15 = D3 = 0: REFT and REFB pins. Note: 0xF0[15] should be set as '1' to enable the external reference mode. Controls phase of LCLK output relative to data 1: Enable deskew pattern mode; 0: Inactive 0 X PAT_DESKEW X 0 PAT_SYNC 1: Enable sync pattern mode; 0: Inactive X EN_2WIRE 1: 2-wire LVDS output; 0: 1-wire LVDS output. Note: ~250us PLL settling time is required after programming the EN_2WIRE bit from Default States After Reset. BTC_MODE 1: 2s complement; (ADC data output format) 0: Binary Offset (ADC data output format) MSB_FIRST 1: MSB First; 0: LSB First 45 1 1 X 1 46 X 1 X 1 1 50 X X X X X FALL_SDR X 1 51 EN_BIT_SER 1 1 X X X X X X 1 X X X X X X X X X X 1 1 EN_SDR X X X X X X X 1 X X X X 1:SDR Bit Clock; 0: DDR Bit Clock Output serialization mode. 0001: 10 bit (EN_10BIT) 0010: 12 bit (EN_12BIT) 0100: 14 bit (EN_14BIT) 1000: 16 bit (EN_16BIT) 1: Controls LCLK rising or falling edge comes in the middle of data window when operating in SDR output mode; 0: At the edge of data window. MAP_Ch1234_to_OUT1A OUT1A Pin pair to channel data mapping selection MAP_Ch1234_to_OUT1B OUT1B Pin pair to channel data mapping selection MAP_Ch1234_to_OUT2A OUT2A Pin pair to channel data mapping selection MAP_Ch1234_to_OUT2B OUT2B Pin pair to channel data mapping selection MAP_Ch1234_to_OUT3A OUT3A Pin pair to channel data mapping selection MAP_Ch1234_to_OUT3B OUT3B Pin pair to channel data mapping selection MAP_Ch1234_to_OUT4A OUT4A Pin pair to channel data mapping selection MAP_Ch1234_to_OUT4B OUT4B Pin pair to channel data mapping selection MAP_Ch5678_to_OUT5B OUT5B Pin pair to channel data mapping selection MAP_Ch5678_to_OUT5A OUT5A Pin pair to channel data mapping selection MAP_Ch5678_to_OUT6B OUT6B Pin pair to channel data mapping selection MAP_Ch5678_to_OUT6A OUT6A Pin pair to channel data mapping selection MAP_Ch5678_to_OUT7B OUT7B Pin pair to channel data mapping selection MAP_Ch5678_to_OUT7A OUT7A Pin pair to channel data mapping selection 52 1 X X X X 1 53 X 1 1 X X X X X X 44 X X X X X X X 1 1 X X 1 54 X X X X X X X X Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Register Maps (continued) Table 6. Summary of Functions Supported by Serial Interface ADDR. (HEX) D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 1 (1)(2)(3)(4) (continued) D3 D2 D1 D0 NAME X X X X MAP_Ch5678_to_OUT8B OUT8B Pin pair to channel data mapping selection DESCRIPTION MAP_Ch5678_to_OUT8A OUT8A Pin pair to channel data mapping selection 55 1 F0 X X X X X EN_EXT_REF 1: Enable external reference mode. the voltage reference can be applied on either REFP and REFB pins or VCM pin. 0: Default: internal reference mode. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 45 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 9.6.1 Description Of Serial Registers 9.6.1.1 Power-Down Modes Table 7. Power-Down Mode Register ADDR. (HEX) 0F D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 NAME X X X X X X X X PDN_CH PDN_PARTIAL PDN_COMPLETE PDN_PIN_CFG X X X Each of the eight channels can be individually powered down. PDN_CH controls the power-down mode for ADC channel . In addition to channel-specific power-down, the ADS5294 also has two global power-down modes: 1. The partial power-down mode partially powers down the chip. Recovery time from the partial power-down mode is about 10 µs provided that the clock has been running for at least 50 µs before exiting this mode. 2. The complete power-down mode completely powers down the chip This mode involves a much longer recovery time 100 µs. In addition to programming the chip in either of these two power-down modes (through either the PDN_PARTIAL or PDN_COMPLETE bits), the PD pin itself can be configured as either a partial power-down pin or a complete power-down pin control. For example, if PDN_PIN_CFG=0 (default), when the PD pin is high, the device enters complete power-down mode. However, if PDN_PIN_CFG=1, when the PD pin is high, the device enters partial power-down mode. 9.6.1.2 Low Frequency Noise Suppression Mode Table 8. Low Frequency Noise Suppression Mode Register ADDR. (HEX) 14 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 NAME X X X X X X X X LFNS_CH The low-frequency noise suppression mode is useful in applications where good noise performance is desired in the frequency band of 0 to 1 MHz (around DC). Setting this mode shifts the low-frequency noise of the ADS5294 to approximately Fs / 2, thereby, moving the noise floor around DC to a much lower value. LFNS_CH enables this mode individually for each channel. See Figure 38 and Figure 39. 9.6.1.3 Analog Input Invert Table 9. Analog Input Invert Register ADDR. (HEX) 24 46 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 NAME X X X X X X X X INVERT_CH Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Generally, INP pin represents the positive analog input pin, and INN represents the complementary negative input. Setting the bits marked INVERT_CH (individual control for each channel) causes the inputs to be swapped. INN now represents the positive input, and INP the negative input. 9.6.1.4 LVDS Test Patterns Table 10. LVDS Test Patterns ADDR. (HEX) 23 24 D15 D14 D13 D12 D11 D10 X X X X X X X X X X X X D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 NAME X X X X X X X X X X X X 0 0 0 X 0 0 0 X X X X X PRBS_SEED PRBS_SEED EN_RAMP DUALCUSTOM_PAT SINGLE_CUSTOM_PAT BITS_CUSTOM1 BITS_CUSTOM2 TP_SOFT_SYNC PRBS_TP_EN 25 X X X X 26 27 X X X X X X X X X X X X X X X X X X X X X X X X X 0 X 45 X 0 PRBS_MODE_2 PRBS_SEED_FROM_REG TP_HARD_SYNC BITS_CUSTOM1 BITS_CUSTOM2 PAT_DESKEW PAT_SYNC The ADS5294 can output a variety of test patterns on the LVDS outputs. These test patterns replace the normal ADC data output. All these patterns can be synchronized across devices by the sync function either through the hardware SYNC pin or the software sync bit TP_SOFT_SYNC bit in register 0x25. When set, the TP_HARD_SYNC bit enables the test patterns to be synchronized by the hardware SYNC Pin. When the software sync bit TP_SOFT_SYNC is set, special timing is needed. • Setting EN_RAMP to '1' causes all the channels to output a repeating full-scale ramp pattern. The ramp increments from zero code to full-scale code in steps of 1 LSB every clock cycle. After hitting the full-scale code, it returns back to zero code and ramps again. • The device can also be programmed to output a constant code by setting SINGLE_CUSTOM_PAT to '1', and programming the desired code in BITS_CUSTOM1. In this mode, BITS_CUSTOM1 take the place of the 14-bit ADC data at the output, and are controlled by LSB-first and MSB-first modes the same way as normal ADC data are controlled. • The device can also toggle between two consecutive codes, by programming DUAL_CUSTOM_PAT to '1'. The two codes are represented by the contents of BITS_CUSTOM1 and BITS_CUSTOM2. • In addition to custom patterns, the device may also be made to output two preset patterns: – Deskew patten – Set using PAT_DESKEW, this mode replaces the 14-bit ADC output D with the 0101010101010101 word. – Sync pattern – Set using PAT_SYNC, the normal ADC word is replaced by a fixed 11111110000000 word. – PRBS patterns – The device can give 9-bit or 23-bit LFSR Pseudo random pattern on the channel outputs that are controlled by the register 0x25. To enable the PRBS pattern PRBS_TP_EN bit in the register 0x25 needs to be set. The default is the 23-bit LFSR. To select the 9-bit LFSR, set the PRBS_MODE_2 bit. The seed value for the PRBS patterns can be chosen by enabling the PRBS_SEED_FROM_REG bit to 1 and the value written to the PRBS_SEED registers in 0x24 and 0x23. NOTE Only one of these patterns should be active at any given instant. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 47 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 9.6.1.5 Bit-Byte-Word Wise Output Table 11. Bit-Byte-Word Wise Output ADDR. (HEX) D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 x 28 NAME EN_BITORDER 1 x 1 BIT_WISE X X X X X X X X EN_WORDWISE_BY_CH Register 0x28 selects the LVDS ADC output as bit-wise, byte-wise, or word-wise in the 2-wire mode. Figure 53 and Figure 54 show the details. Sample N-1 Input Signal Sample N ta td cycles latency Input Clock CLKIN Freq = fCLKIN Frame Clock FCLK Freq = f CLKIN/2 Output Data CHnOUT B Byte-wise Output Data CHnOUT A Byte-wise Output Data CHnOUT B Bit-wise Output Data CHnOUT A Bit-wise Output Data CHnOUT B Word-wise (Sample N) Output Data CHnOUT A Word-wise (Sample N-1) D6 (D5) D11 (D0) D10 (D1) D9 (D2) D8 (D3) D1 D0 (D10) (D11) D5 (D6) D4 (D7) D3 (D8) D2 (D9) D7 (D4) D6 (D5) D11 (D0) D10 (D1) D9 (D2) D8 (D3) D1 D0 (D10) (D11) D5 (D6) D4 (D7) D3 (D8) D2 (D9) D7 (D4) D7 (D4) D6 (D5) D1 D0 (D10) (D11) D2 (D9) D0 (D11) D10 (D1) D8 (D3) D6 (D5) D4 (D7) D2 (D9) D0 (D11) D10 (D1) D8 (D3) D6 (D5) D4 (D7) D2 (D9) D0 (D11) D3 (D8) D1 (D10) D11 (D0) D9 (D2) D7 (D4) D5 (D6) D3 (D8) D1 (D10) D11 (D0) D9 (D2) D7 (D4) D5 (D6) D3 (D8) D1 (D10) D1 D0 (D10) (D11) D11 (D0) D10 (D1) D9 (D2) D8 (D3) D7 (D4) D6 (D5) D5 (D6) D4 (D7) D3 (D8) D2 (D9) D1 D0 (D10) (D11) D1 D0 (D10) (D11) D11 (D0) D10 (D1) D9 (D2) D8 (D3) D7 (D4) D6 (D5) D5 (D6) D4 (D7) D3 (D8) D2 (D9) D1 D0 (D10) (D11) D11 (D0) Data bit in MSB First mode Data bit in LSB First mode Figure 53. 12-Bit Word Wise 48 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Sample N-1 Input Signal Sample N ta td cycles latency Input Clock CLKIN Freq = fCLKIN Frame Clock FCLK Freq = fCLKIN/2 Output Data CHnOUT B Byte-wise D8 (D5) D7 (D6) D13 (D0) D12 (D1) D11 (D2) Output Data CHnOUT A Byte-wise D1 D0 (D12) (D13) D6 (D7) D5 (D8) D4 (D9) Output Data CHnOUT B Bit-wise D2 D0 (D11) (D13) D12 (D1) D10 (D3) D8 (D5) D6 (D7) D4 (D9) Output Data CHnOUT A Bit-wise D3 D1 (D10) (D12) D13 (D0) D11 (D2) D9 (D4) D7 (D6) D5 (D8) D1 D0 (D12) (D13) D13 (D0) D12 (D1) D11 (D2) D10 (D3) D9 (D4) D8 (D5) D1 D0 (D12) (D13) D13 (D0) D12 (D1) D11 (D2) D10 (D3) D9 (D4) D8 (D5) Output Data CHnOUT B Word-wise (Sample N) Output Data CHnOUT A Word-wise (Sample N-1) D13 (D0) D9 (D4) D8 (D5) D7 (D6) D7 (D6) D13 (D0) D12 (D1) D11 (D2) D2 D1 D0 D3 (D10) (D11) (D12) (D13) D6 (D7) D5 (D8) D4 (D9) D2 D1 D0 D3 (D10) (D11) (D12) (D13) D2 D0 (D11) (D13) D12 (D1) D10 (D3) D8 (D5) D6 (D7) D4 (D9) D2 D0 (D11) (D13) D3 D1 (D10) (D12) D13 (D0) D11 (D2) D9 (D4) D7 (D6) D5 (D8) D3 D1 (D10) (D12) D7 (D6) D6 (D7) D5 (D8) D4 (D9) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D7 (D6) D6 (D7) D5 (D8) D4 (D9) D3 D2 D1 D0 (D10) (D11) (D12) (D13) D10 (D3) D9 (D4) D8 (D5) D10 (D3) Data bit in MSB First mode Data bit in LSB First mode Figure 54. 14-Bit Word Wise 9.6.1.6 Digital Processing Blocks The ADS5294 integrates a set of commonly-used digital functions to ease system design. These functions are shown in the digital block diagram of Figure 55 and described in the following sections. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 49 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Test Patterns Channel 1 ADC Data - 14-BIT Ramp Average of 2 channels Built-in Coefficients 24-tap filter (Even Tap) 23-tap filter (Odd Tap) Channel 2 ADC Data Channel 3 ADC Data Channel 4 ADC Data Average of 4 channels Decimation by 2 or by 4 23-tap filter (Odd Tap) 12-tap filter OUT 1A Serializer Wire 2 OUT 1B Channel 2 Serializer Wire 1 OUT 2A Serializer Wire 2 Custom Coefficients 24-tap filter (Even Tap) LVDS OUTPUTS Channel 1 Serializer Wire 1 Decimation by 2 or by 4 or by 8 GAIN (0 to 12 dB , 1 dB steps ) MAPPER Channel 3 Serializer Wire 1 MULTIPLEXER 8:8 CHANNEL 1 OUT 3A OUT 3B Serializer Wire 2 OUT 4A Channel 4 Serializer Wire 1 DIGITAL PROCESSING BLOCK for OUT 2B OUT 4B Serializer Wire 2 ½ ADS529x Figure 55. Digital Processing Block Diagram 50 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 9.6.1.7 Programmable Digital Gain Table 12. Programmable Digital Gain ADDR. (HEX) 2A 2B D15 X X D14 X X D13 X X D12 D11 D10 D9 D8 X X X X X X X X D7 D6 D5 D4 X X X X X X X X D3 D2 D1 D0 NAME X X X X X X X X GAIN_CH1 GAIN_CH2 GAIN_CH3 GAIN_CH4 GAIN_CH5 GAIN_CH6 GAIN_CH7 GAIN_CH8 X X In applications where the full-scale swing of the analog input signal is much less than the 2 VPP range supported by the ADS5294, a programmable gain is set to achieve the full-scale output code even with a lower analog input swing. The programmable gain for each channel is set individually using a set of four bits, indicated as GAIN_CHN for Channel N. The gain setting is coded in binary from 0 to 12 dB as shown in Table 13. Table 13. Gain Setting for Channel N GAIN_CHN GAIN_CHN GAIN_CHN GAIN_CHN CHANNEL N GAIN SETTING 0 0 0 0 0 dB 0 0 0 1 1 dB 0 0 1 0 2 dB 0 0 1 1 3 dB 0 1 0 0 4 dB 0 1 0 1 5 dB 0 1 1 0 6 dB 0 1 1 1 7 dB 1 0 0 0 8 dB 1 0 0 1 9 dB 1 0 1 0 10 dB 1 0 1 1 11 dB 1 1 0 0 12 dB 1 1 0 1 Do not use 1 1 1 0 Do not use 1 1 1 1 Do not use 9.6.1.8 Channel Averaging Table 14. Channel Averaging ADDR. (HEX) 29 2C D15 D14 D13 D12 D11 D10 D9 X X D8 D7 X D6 D5 D4 X D2 D1 D0 NAME X EN_CHANNEL_AVG AVG_CTRL4 AVG_CTRL3 AVG_CTRL2 AVG_CTRL1 AVG_CTRL8 AVG_CTRL7 AVG_CTRL6 AVG_CTRL5 X X 2D D3 X X X X X X X X X X Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 51 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com In the default mode of operation, the LVDS outputs contain the data of the ADC Channels . By setting the EN_CHANNEL_AVG bit to ‘1’, the outputs from multiple channels can be averaged. The resulting outputs from the Channel averaging block (which is bypassed in the default mode) are referred to as Bins. The contents of the Bins come out on the LVDS outputs . The contents of each of the eight Bins are determined by the register bits marked AVG_CTRLn where n stands for the Bin number. The different settings are shown in the following table: Table 15. Channel Averaging 52 AVG_CTRL1 AVG_CTRL1 Contents of Bin 1 0 0 Zero 0 1 ADC Channel 1 1 0 Average of ADC Channel 1, 2 1 1 Average of ADC Channel 1, 2, 3, 4 AVG_CTRL2 AVG_CTRL2 Contents of Bin 2 0 0 Zero 0 1 ADC Channel 2 1 0 ADC Channel 3 1 1 Average of ADC Channel 3, 4 AVG_CTRL3 AVG_CTRL3 Contents of Bin 3 0 0 Zero 0 1 ADC Channel 3 1 0 ADC Channel 2 1 1 Average of ADC Channel 1, 2 AVG_CTRL4 AVG_CTRL4 Contents of Bin 4 0 0 Zero 0 1 ADC Channel 4 1 0 Average of ADC Channel 3, 4 1 1 Average of ADC Channel 1, 2, 3, 4 AVG_CTRL5 AVG_CTRL5 Contents of Bin 5 0 0 Zero 0 1 ADC Channel 5 1 0 Average of ADC Channel 5, 6 1 1 Average of ADC Channel 5, 6, 7, 8 AVG_CTRL6 AVG_CTRL6 Contents of Bin 6 0 0 Zero 0 1 ADC Channel 6 1 0 ADC Channel 7 1 1 Average of ADC Channel 7, 8 AVG_CTRL7 AVG_CTRL7 Contents of Bin 7 0 0 Zero 0 1 ADC Channel 7 1 0 ADC Channel 6 1 1 Average of ADC Channel 6, 5 AVG_CTRL8 AVG_CTRL8 Contents of Bin 8 0 0 Zero 0 1 ADC Channel 8 1 0 Average of ADC Channel 7, 8 1 1 Average of ADC Channel 5, 6, 7, 8 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 When the contents of a particular Bin is set to zero, then the LVDS buffer corresponding to that Bin gets automatically powered down. 9.6.1.9 Decimation Filter Table 16. Decimation Filter ADDR. (HEX) D15 D14 D13 D12 D11 D10 D9 D8 D7 X X X D6 D5 D4 D3 D2 29 2E D1 D0 X GLOBAL_EN_FILTER FILTER1_COEFF_SET X X X FILTER1_RATE X ODD_TAP1 X 2F X X X X X FILTER2_RATE X ODD_TAP2 X X X X X X FILTER3_RATE X ODD_TAP3 X X X X X X FILTER4_RATE X ODD_TAP4 X X X X X X FILTER5_RATE X ODD_TAP5 X X X X X X FILTER6_RATE X ODD_TAP6 X X X X X X FILTER7_RATE X ODD_TAP7 X X X USE_FILTER6 FILTER7_COEFF_SET X 35 USE_FILTER5 FILTER6_COEFF_SET X 34 USE_FILTER4 FILTER5_COEFF_SET X 33 USE_FILTER3 FILTER4_COEFF_SET X 32 USE_FILTER2 FILTER3_COEFF_SET X 31 USE_FILTER1 FILTER2_COEFF_SET X 30 NAME X USE_FILTER7 FILTER8_COEFF_SET X X X FILTER8_RATE X ODD_TAP8 X USE_FILTER8 The decimation filter is implemented as 24-tap FIR with symmetrical coefficients (each coefficient is 12-bit signed). The filter equation is: æ 1 ö y(n) = ç ÷ ´ ëé(h0 ´ x(n)+h1 ´ x(n - 1)+h2 ´ x(n - 2)+...+h11 ´ x(n - 11)+h11 ´ x(n - 12)...+h1 ´ x(n - 22)+h0 ´ x(n - 23)ûù è 211 ø (2) By setting the register bit = 1, a 23-tap FIR is implemented: æ 1 ö y(n)= çç ÷ ´ é(h ´ x(n)+h1 ´ x(n - 1)+h2 ´ x(n - 2)+...+h10 ´ x(n - 10)+h11 ´ x(n - 11)+h10 ´ x(n - 12)...+h1 ´ x(n - 21)+h0 ´ x(n - 22)ùû 11 ÷ ë 0 è2 ø (3) In Equation 2 and Equation 3, h0, h1 …h11 are 12-bit signed representation of the coefficients, x(n) is the input data sequence to the filter and y(n) is the filter output sequence. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 53 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com A decimation filter can be introduced at the output of each channel. To enable this feature, the GLOBAL_EN_FILTER should be set to ‘1’. Setting this bit to ‘1’ increases the overall latency of each channel to 20 clock cycles irrespective of whether the filter for that particular channel has been chosen or not (using the USE_FILTER bit). The bits marked FILTERn_COEFF_SET, FILTERn_RATE, ODD_TAPn and USE_FILTERn represent the controls for the filter for Channel n. Note that these bits are functional only when the GLOBAL_EN_FILTER gets set to '1' and USE_FILTERn bit is set to '1'. For illustration, the controls for channel 1 are listed in Table 17: The USE_FILTER1 bit determines whether the filter for Channel 1 is used or not. When this bit is set to ‘1’, the filter for channel 1 is enabled. When this bit is set to ‘0’, the filter for channel 1 is disabled but the channel data passes through a dummy delay so that the overall latency of channel 1 is 20 clock cycles. With the USE_FILTER1 bit set to ‘1’, the characteristics of the filter can be set by using the other sets of bits. The ADS5294 has six sets of filter coefficients stored in memory. Each of these sets define a unique pass band in the frequency domain and contain 12 coefficients (each coefficient is 12-bit long). These 12 coefficients are used to implement either a symmetric 24-tap (even-tap) filter, or a symmetric 23-tap (odd-tap) filter. Setting the register bit ODD_TAP1 to ‘1’ enables the odd-tap configuration (the default is even tap with this bit set to ‘0’) for Channel 1. The bits FILTER1_COEFF_SET are used to choose the required set of coefficients for Channel 1. The passbands corresponding to of each of these filter coefficient sets is shown in Figure 56 Set 1 H(f) H(f) 0.2*Fs 0.3*Fs f 0.2*Fs Set 3 H(f) H(f) 0.1*Fs Set 2 f 0.125*Fs Set 5 H(f) H(f) 0.275*Fs 0.225*Fs 0.5*Fs f Set 4 0.075*Fs 0.15*Fs 0.3*Fs 0.275*Fs 0.225*Fs f Set 6 f 0.375*Fs 0.4*Fs 0.5*Fs f 0.35*Fs Figure 56. Filter Types Coefficient Sets 1 and 2 are the most appropriate when decimation by a factor of 2 is required, whereas Coefficient Sets 3, 4, 5, and 6 are appropriate when decimation by a factor of 4 is desired. The computation rate of the filter output is set independently using the bits FILTERn_RATE. The settings are shown in Table 17. 54 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Table 17. Digital Filters DATA_RAT E> FILTERn_RA TE FILTERn_CO EFF_SET ODD_TAP USE_FILTE R_CHn EN_CUSTOM_ FILT Built-in low-pass odd-tap filter (pass band = 0 to fS/4) 01 000 000 1 1 0 Built-in highpass odd-tap filter (pass band = fS/4 to fS/2 ) 01 000 001 1 1 0 Built-in lowpass even-tap filter (pass band = 0 to fS/8) 10 001 010 0 1 0 Built-in first bandpass even tap filter(pass band = fS/8 to fS/4) 10 001 011 0 1 0 Built-in second bandpass even tap filter(pass band = fS/4 to 3 fS/8) 10 001 100 0 1 0 DECIMATION Decimate by 2 Decimate by 4 TYPE OF FILTER Built-in highpass odd tap filter (pass band = 3 fS/8 to fS/2) 10 001 101 1 1 0 Decimate by 2 Custom filter (user-programmable coefficients) 01 000 000 0 and 1 1 1 Decimate by 4 Custom filter (user-programmable coefficients) 10 001 000 0 and 1 1 1 Decimate by 8 Custom filter (user-programmable coefficients) 11 100 000 0 and 1 1 1 Bypass decimation Custom filter (user-programmable coefficients) 00 011 000 0 and 1 1 1 Note: EN_CUSTOM_FILT is the D15 of register 5A (Hex) to B9 (Hex). The choice of the odd or even tap setting, filter coefficient set, and the filter rate uniquely determines the filter to be used. In addition to the preset filter coefficients, the coefficients for each of the eight filter channels can be programmed by the user. Each of the eight channels has 12 programmable coefficients, each 12-bit long. The 96 registers with addresses from 5A (Hex) to B9 (Hex) are used to program these eight sets of 12 programmable coefficients. Registers 5A to 65 are used to program the first filter, with the first coefficient occupying the bits D11..D0 of register 5A, the second coefficient occupying the bits D11..D0 of register 5B, and so on. Similarly registers 66 (Hex) to 71 (Hex) are used to program the second filter, and so on. When programming the filter coefficients, the D15 bit, EN_CUSTOM_FILT, of each of the 12 registers corresponding to that filter should be set to ‘1’. If the D15 bit of these 12 registers is set to ‘0’, then the preset coefficient (as programmed by FILTERn_COEFF_SET) is used even if the bits D11..D0 get programmed. By setting or not setting the D15 bits of individual filter channels to ‘1’, some filters can be made to operate with preset coefficient sets, and some others can be made to simultaneously operate with programmed coefficient sets. 9.6.1.10 Highpass Filter Table 18. Highpass Filter ADDR. (HEX) 2E 2E 2F 2F 30 30 31 31 32 32 33 33 34 34 35 35 D15 D14 D13 D12 D11 D10 X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 NAME HPF_corner_CH1 HPF_EN_CH1 HPF_corner_CH2 HPF_EN_CH2 HPF_corner_CH3 HPF_EN_CH3 HPF_corner_CH4 HPF_EN_CH4 HPF_corner_CH5 HPF_EN_CH5 HPF_corner_CH6 HPF_EN_CH6 HPF_corner_CH7 HPF_EN_CH7 HPF_corner_CH8 HPF_EN_CH8 X X X X X X X X This group of registers controls the characteristics of a digital highpass transfer function applied to the output data, using Equation 4: y(n) = 2 k k 2 +1 [x(n) - x(n - 1)+y(n - 1)] where Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 55 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 • www.ti.com k is set as described by the HPF_corner registers (one for each channel). (4) The HPF_EN bit in each register must be set to enable the HPF feature for each channel. 9.6.1.11 Bit-Clock Programmability Table 19. Bit-Clock Programmability ADDR. (HEX) 42 46 46 D15 D14 1 1 D13 D12 D11 D10 D9 D8 D7 D6 D5 X X D4 D3 D2 D1 D0 NAME PHASE_DDR EN_SDR FALL_SDR X X The output interface of the ADS5294 is normally a DDR interface, with the LCLK rising edge and falling edge transitions in the middle of alternate data windows. This default phase is shown in Figure 57. PHASE_DDR = 10 ADCLKp LCLKp OUTp Figure 57. Default Phase of LCLK The phase of LCLK is programmed relative to the output frame clock and data using bits PHASE_DDR. The LCLK phase modes are shown in Figure 58. PHASE_DDR = 00 PHASE_DDR = 10 ADCLKp ADCLKp LCLKp LCLKp OUTp OUTp PHASE_DDR = 01 PHASE_DDR = 11 ADCLKp ADCLKp LCLKp LCLKp OUTp OUTp Figure 58. Phase Programmability Modes for LCLK 56 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 In addition to programming the phase of the LCLK in the DDR mode, the device also operates in SDR mode by setting bit EN_SDR to 1. In SDR mode, the bit clock (LCLK) is output at 14-times the input clock, or twice the rate as in DDR mode. Depending on the state of FALL_SDR, the LCLK may be output in either of the two manners shown in Figure 59. As can be seen in Figure 59, only the LCLK rising (or falling edge) is used to capture the output data in SDR mode. The SDR mode does not work well beyond 40 MSPS because the LCLK frequency will become very high. EN_SDR = 1, FALL_SDR = 0 ADCLKp LCLKp OUTp EN_SDR = 1, FALL_SDR = 1 ADCLKp LCLKp OUTp Figure 59. SDR Interface Modes 9.6.1.12 Output Data Rate Control Table 20. Output Data Rate Control ADDR. (HEX) 38 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 DATA_RATE DATA_RATE In the default mode of operation, the data rate at the output of the ADS5294 is at the sampling rate of the ADC which is true even when the custom pattern generator is enabled. In addition, both output data rate and sampling rate can be configured to a sub-multiple of the input clock rate. With the DATA_RATE control, the output data rate is programmed to be a sub-multiple of the ADC sampling rate. This feature is used to lower the output data rate, for example, when the decimation filter is used. Without enabling the decimation filter, the sub-multiple ADC sampling rate feature is used. The different settings are listed in Table 21. Table 21. Output Data Rates DATA_RATE DATA_RATE OUTPUT DATA RATE 0 0 Same as ADC sampling rate 0 1 1 / 2 of ADC sampling rate 1 0 1 / 4 of ADC sampling rate Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 57 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Table 21. Output Data Rates (continued) DATA_RATE DATA_RATE OUTPUT DATA RATE 1 1 1 / 8 of ADC sampling rate 9.6.1.13 Synchronization Pulse Table 22. Synchronization Pulse ADDR. (HEX) 25 02 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 TP_HARD_SYNC EN_SYNC The SYNC pin synchronizes the data output from channels within the same chip or from channels across chips when decimation filters are used with reduced output data rate. When the decimation filters are used (for example, the decimate-by-two filter is enabled), then, effectively, the device outputs one digital code for every two analog input samples. If the SYNC function is not enabled, then the filters are not synchronized (even within a chip) which means that one channel is sending out codes corresponding to input samples N, N + 1 and so on, while another may be sending out code corresponding to N + 1, N + 2, and so on. To achieve synchronization, the SYNC pulse must arrive at all the ADS529x chips at the same time instant (as shown in the timing diagram of Figure 60 The ADS5294 generates an internal synchronization signal which is used to reset the internal clock dividers used by the decimation filter. Using the SYNC signal in this way ensures that all channels will output digital codes corresponding to the same set of input samples. SYNC Timings: Synchronizing the filters using the SYNC pin is enabled by default. No register bits are required to be written. Even EN_SYNC bit is not required.It is important for register bit TP_HARD_SYNC to be 0 for this mode to work. As shown by Figure 60, the SYNC rising edge can be positioned anywhere within the window. The width of the SYNC must be at least one clock cycle. 0ns ADC Input Clock t CLK/2 -1ns t CLK/2 td: -1 ns< td < t CLK/2 SYNC twidth > 1clock cycle Figure 60. Synchronization Pulse Timing Note that the SYNC DOES NOT synchronize the sampling instants of the ADC across chips. All channels within a single chip sample their analog inputs simultaneously. The input clock needs to be routed to both chips with identical length to ensure that channels across two chips will sample their analog inputs simultaneously. Taking this step ensures that the input clocks arrive at both of the chips at the same time. This should be handled in the board design and routing. The SYNC pin cannot be used to synchronize the sampling instants. 58 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 In addition to the above, the SYNC also synchronizes the RAMP test patterns across channels. In order to synchronize the test patterns, TP_HARD_SYNC must be set as '1'. Setting TP_HARD_SYNC = 1 actually disables the sync of the filters. 9.6.1.14 External Reference Mode of Operation The ADS5294 supports an external reference mode of operation in one of two ways: a. By forcing the reference voltages on the REFT and REFB pins. b. By applying the reference voltage on VCM pin. This mode can be used to operate multiple ADS5294 chips with the same (externally applied) reference voltage. Using the REF pins: For normal operation, the device requires two reference voltages: REFT and REFB. By default, the device generates these two voltages internally. To enable the external reference mode, set the register bits as shown in Table 23 which powers down the internal reference amplifier and the two reference voltages are forced directly on the REFT and REFB pins as VREFT = 1.45 V ± 50 mV and VREFB = 0.45 V ±50 mV. Note that the relation between the ADC full-scale input voltage and the applied reference voltages is Full-scale input voltage = 2 × (VREFT – VREFB) (5) Using the VCM pin: In this mode, an external reference voltage VREFIN can be applied to the VCM pin such that Full-scale input voltage = 2 × VREFIN x (2 / 3) (6) To enable this mode, set the register bits as shown in Table 23 which changes the function of the VCM pin to an external reference input pin. The voltage applied on VCM must be 1.5 V ±50 mV. Table 23. External Reference Function EN_HIGH_ADDRS ( 0x1[4]) EN_EXT_REF (0xF0[15]) EXT_REF_VCM (0x42[15,3]) External reference using REFT and REFB pins 1 1 00 External reference using VCM pin 1 1 11 Function 9.6.1.15 Data Output Format Modes Table 24. Data Output Format Modes ADDR. (HEX) 46 46 D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 1 1 D4 D3 D2 X X D1 D0 NAME BTC_MODE MSB_FIRST Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 59 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com By default, the ADC output is in straight-offset binary mode. Programming the BTC_MODE bit to '1' inverts the MSB, and the output becomes Binary 2s-complement mode. Also by default, the first bit of the frame (following the rising edge of CLKP) is the LSB of the ADC output. Programming the MSB_FIRST mode inverts the bit order in the word, and the MSB is output as the first bit following CLKP rising edge. 9.6.1.16 Programmable Mapping Between Input Channels and Output Pins Table 25. Mapping Between Input Channels and Output Pins ADDR. D15 D14 D13 D12 D11 D10 (HEX) 50 1 1 1 X X 51 1 1 1 X X 52 1 1 53 54 55 1 1 1 1 1 1 1 1 X X X X D9 X X X X D8 D7 D6 D5 D4 X X X X X X X X X X X X X X X X X X X X X X X X X D3 D2 D1 D0 NAME X X X X X X X X X X X MAP_CH1234_TO_OUT1A MAP_CH1234_TO_OUT1B MAP_CH1234_TO_OUT2A MAP_CH1234_TO_OUT2B MAP_CH1234_TO_OUT3A MAP_CH1234_TO_OUT3B MAP_CH1234_TO_OUT4A MAP_CH1234_TO_OUT4B X X X X X X X X X X X X X X X X MAP_CH5678_TO_OUT5B MAP_CH5678_TO_OUT5A MAP_CH5678_TO_OUT6B MAP_CH5678_TO_OUT6A MAP_CH5678_TO_OUT7B MAP_CH5678_TO_OUT7A MAP_CH5678_TO_OUT8B MAP_CH5678_TO_OUT8A The ADS5294 has 16 pairs of LVDS channel outputs. The mapping of ADC channels to LVDS output channels is programmable to allow for flexibility in board layout. The 16 LVDS channel outputs are split into two groups of eight LVDS pairs. Within each group four ADC input channels are multiplexed into the eight LVDS pairs depending on the modes of operation whether it is in 1-wire mode or 2-wire mode. Input channels 1 to 4 map to any of the LVDS outputs OUT1A or OUT1B to OUT4A or OUT4B (using the MAP_CH1234_TO_OUTnA or OUTnB). Similarly, input channels 5 to 8 can be mapped to any of the LVDS outputs OUT5A or OUT5B to OUT8A or OUT8B (using the MAP_CH5678_TO_OUTnA or OUTnB). The block diagram of the mapping is listed in Figure 61. 60 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Channel 8 data MAP_CH5678_to_OUTn = 0000 n = 5A, 5B, 6A, 6B, 7A, 7B, 8A, 8B Channel 7 data MAP_CH5678_to_OUTn = 0010 OUTn Channel 6 data MAP_CH5678_to_OUTn = 0100 Channel 5 data MAP_CH5678_to_OUTn = 0110 MAP_CH5678_to_OUTn = 1xxx, the unused OUTn LVDS buffer is powered down. Channel 4 data MAP_CH1234_to_OUTn = 0110 Channel 3 data MAP_CH1234_to_OUTn = 0100 OUTn Channel 2 data MAP_CH1234_to_OUTn = 0010 Channel 1 data MAP_CH1234_to_OUTn = 0000 MAP_CH1234_to_OUTn = 1xxx, the unused OUTn LVDS buffer is powered down. (a) 1-wire mode Channel 1 LSB Byte data MAP_CH1234_to_OUTn = 0000 Channel 1 MSB Byte data MAP_CH1234_to_OUTn = 0001 Channel 2 LSB Byte data MAP_CH1234_to_OUTn = 0010 n = 1A, 1B, 2A, 2B, 3A, 3B, 4A, 4B Channel 2 MSB Byte data MAP_CH1234_to_OUTn = 0011 OUTn Channel 3 LSB Byte data MAP_CH1234_to_OUTn = 0100 Channel 3 MSB Byte data MAP_CH1234_to_OUTn = 0101 MAP_CH1234_to_OUTn = 1xxx, the unused OUTn LVDS buffer is powered down. Channel 4 LSB Byte data MAP_CH1234_to_OUTn = 0110 Channel 4 MSB Byte data MAP_CH1234_to_OUTn = 0011 Channel 8 LSB Byte data MAP_CH5678_to_OUTn = 0000 Channel 8 MSB Byte data MAP_CH5678_to_OUTn = 0001 Channel 7 LSB Byte data MAP_CH5678_to_OUTn = 0010 n = 5A, 5B, 6A, 6B, 7A, 7B, 7A, 7B Channel 7 MSB Byte data MAP_CH5678_to_OUTn = 0011 OUTn Channel 6 LSB Byte data MAP_CH5678_to_OUTn = 0100 Channel 6 MSB Byte data MAP_CH5678_to_OUTn = 0101 MAP_CH5678_to_OUTn = 1xxx, the unused OUTn LVDS buffer is powered down. Channel 5 LSB Byte data MAP_CH5678_to_OUTn = 0110 Channel 5 MSB Byte data MAP_CH5678_to_OUTn = 0011 (b) 2-wire mode Figure 61. Input and Output Channel Mapping Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 61 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Registers 0x50 to 0x55 control the multiplexing options as shown in Table 26 and Table 27. Table 26. Multiplexing Options MAP_CH1234_to_OUTn MAPPING USED IN 1-WIRE MODE? USED IN 2-WIRE MODE? 0000 ADC input channel IN1 to OUTn Y Y, for LSB byte 0001 ADC input channel IN1 to OUTn (2wire only) N Y, for MSB byte 0010 ADC input channel IN2 to OUTn Y Y, for LSB byte 0011 ADC input channel IN2 to OUTn (2wire only) N Y, for MSB byte 0100 ADC input channel IN3 to OUTn Y Y, for LSB byte 0101 ADC input channel IN3 to OUTn (2wire only) N Y, for MSB byte 0110 ADC input channel IN4 to OUTn Y Y, for LSB byte 0111 ADC input channel IN4 to OUTn (2wire only) N Y, for MSB byte 1xxx LVDS output buffer OUTn is powered down Table 27. Multiplexing Options MAP_CH5678_to_OUTn 62 MAPPING USED IN 1-WIRE MODE? USED IN 2-WIRE MODE? 0000 ADC input channel IN8 to OUTn Y Y, for LSB byte 0001 ADC input channel IN8 to OUTn (2wire only) N Y, for MSB byte 0010 ADC input channel IN7 to OUTn Y Y, for LSB byte 0011 ADC input channel IN7 to OUTn (2wire only) N Y, for MSB byte 0100 ADC input channel IN6 to OUTn Y Y, for LSB byte 0101 ADC input channel IN6 to OUTn (2wire only) N Y, for MSB byte 0110 ADC input channel IN5 to OUTn Y Y, for LSB byte 0111 ADC input channel IN5 to OUTn (2wire only) N Y, for MSB byte 1xxx LVDS output buffer OUTn is powered down Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 The default mapping for 1-wire and 2-wire modes is shown in Table 28 and Table 29. Table 28. Mapping for 1-Wire Mode (1) (1) ANALOG INPUT CHANNEL LVDS OUTPUT Channel IN1 OUT1A Channel IN2 OUT2A Channel IN3 OUT3A Channel IN4 OUT4A Channel IN5 OUT5A Channel IN6 OUT6A Channel IN7 OUT7A Channel IN8 OUT8A 3In the single wire mode with default register settings, ADC data is available only on OUTnA. Table 29. Mapping for 2-Wire Mode (1) (1) ANALOG INPUT CHANNEL LVDS OUTPUT Channel IN1 OUT1A, OUT1B Channel IN2 OUT2A, OUT2B Channel IN3 OUT3A, OUT3B Channel IN4 OUT4A, OUT4B Channel IN5 OUT5A, OUT5B Channel IN6 OUT6A, OUT6B Channel IN7 OUT7A, OUT7B Channel IN8 OUT8A, OUT8B In the 2-wire mode, the ADC data is available on both OUTnA and OUTnB. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 63 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 10 Application and Implementation NOTE Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality. 10.1 Application Information The design procedures are discussed in the following sections. Device Comparison Table shows related devices suitable for high-speed, multi-channel data acquisition. Figure 62 lists a typical application circuit diagram. 64 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 10.2 Typical Application 1.8VA 1.8VD 10uF AVSS 0.1uF 10uF N*0.1uF AGND N*0.1uF LGND AVDD 10Ÿ LVDD IN1P OUT1A_P OUT1A_N 2pF 0.1uF 0.1uF 10Ÿ IN1N IN1P 0.1uF OUT1B_P OUT1B_N 10Ÿ 2pF IN2N 0.1uF 0.1uF 10Ÿ OUT2B_P OUT2B_N 10Ÿ IN3P OUT3A_P OUT3A_N IN3N 10Ÿ OUT3B_P OUT3B_N 10Ÿ OUT4A_P OUT4A_N 2pF 0.1uF 0.1uF IN4P IN4N ADS5294/92 10Ÿ IN5P CSZ RESET PD SYNC LCLKP LCLKN OUT5A_P OUT5A_N 10Ÿ IN6P OUT5B_P OUT5B_N IN6N OUT6A_P OUT6A_N 10Ÿ 10Ÿ IN7P OUT6B_P OUT6B_N IN7N OUT7A_P OUT7A_N 2pF 10Ÿ OUT7B_P OUT7B_N 10Ÿ IN8P OUT8A_P OUT8A_N 2pF IN8N 0.1uF ADS5294/92 SCLK 10Ÿ 2pF 0.1uF 0.1uF SDATA ACLKP ACLKN IN5N 0.1uF 0.1uF RCLKT 100Ÿ SOUT 10Ÿ 2pF 0.1uF 0.1uF 0.1uF OUT4B_P OUT4B_N 2pF 0.1uF 0.1uF CLKN OUT2A_P OUT2A_N IN2P CLKP 10Ÿ OUT8B_P OUT8B_N REFB(0.45V Vout or Vin) REFT(1.45V Vout or Vin) VCM (0.95V Vout or 1.5V Vin) SEE 0x42[15,3] FOR VCM, REFB/T PINS 1uF 1uF 1uF (Optional) (1) AGND NC LGND REFB, REFT pins can be left floating in the internal reference mode, i.e. EN_EXT_REF=0. Figure 62. Application Circuit Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 65 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Typical Application (continued) 10.2.1 Design Requirements The ADS5294 is a high-speed, multi-channel ADC suitable for medical imaging, communication systems, multichannel data acquisition, and so on. In all applications, the signal dynamic range, center frequency, and bandwidth are the key requirements for the ADC selection. The ADS5294 has a noise level of approximately 20 nV/√Hz referred to its input, assuming of a sampling rate of 80 MHz, a 2-Vpp input, and 75.5-dBFS SNR. Suitable ADS5294 driver circuit shall be designed to achieve better than 20 nV/√Hz output referred noise. 10.2.2 Detailed Design Procedure Use the following steps to design a typical data acquistion system: 1. Use the signal center frequency and signal bandwidth to select an appropriate ADC sampling frequency. 2. Use the transducer or sensor noise level and maximum input signal amplitude to select appropriate predriver amplifiers. 3. Select appropriate low jitter clock for the ADC. 4. Determine whether to use the on-chip digital filters or decimation filters based on required SNR and pass band shaping. 10.2.2.1 Large and Small Signal Input Bandwidth The small signal bandwidth of the analog input circuit is high, around 550 MHz. When using an amplifier to drive the ADS5294, consider the total noise of the amplifier up to the small signal bandwidth. The large signal bandwidth of the device depends on the amplitude of the input signal. The ADS5294 supports 2 VPP amplitude for input signal frequency up to 80 MHz. For higher frequencies (80 MHz), the amplitude of the input signal must be decreased proportionally. For example, at 160 MHz, the device supports a maximum of 1 VPP signal. 10.2.2.2 Drive Circuit For optimum performance, the analog inputs must be driven differentially which improves the common-mode noise immunity and even order harmonic rejection. A 5-Ω to 15-Ω resistor in series with each input pin is recommended to damp-out ringing caused by package parasitic. The drive circuit shows an R-C filter across the analog input pins. The purpose of the filter is to absorb the glitches caused by the opening and closing of the sampling capacitors. The output of the driver circuit referred noise shall be considered in order to maximize SNR of the ADS5294. 0.1uF 10 INP Differential Input 2 pF INM 0.1uF 10 ADS529x Figure 63. Analog Input Drive Circuit 10.2.2.3 Clock Selection To ensure that the aperture delay and jitter are the same for all channels, the ADS5294 uses a clock tree network to generate individual sampling clocks for each channel. The clock, for all the channels, are matched from the source point to the sampling circuit of each of the eight internal ADCs. The variation on this delay is described in the aperture delay parameter of the output interface timing. Its variation is given by the aperture jitter number of the same table. 66 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 Typical Application (continued) The ADS5294 clock input can be driven by either a differential clocks (sine wave, LVPECL, or LVDS) or a singled clock(LVCMOS). In the single-ended case, TI recommends that the use of low jitter square signals (LVCMOS levels, 1.8-V amplitude). See TI document SLYT075 for further details on the theory. The jitter cleaner CDCM7005 SCAS793, CDCE72010 SLAS490, LMK04803 SNAS489 is suitable to generate the ADC clock of the ADS5294 and ensure the performance for the14-bit ADC with >75-dBFS SNR. Please note that the location of LVDS Rterm depends on the LVDS clock driver. Some clock devices require the Rterm at the left side of AC coupling capacitors. SINGLE-ENDED CLOCK CONNECTIONS CMOS CLOCK IN CLKP VCM CLKM ADS529x Figure 64. Single-Ended Clock Drive Circuit DIFFERENTIAL CLOCK CONNECTIONS 0.1 mF 0.1 mF CLKP CLKP Differential LVPECL clock input Differential sinewave clock input Rterm 0.1 mF CLKM 0.1 mF CLKM Rterm ADS529x ADS529x 0.1 mF CLKP Differential LVDS clock input Rterm CLKM 0.1 mF ADS529x Figure 65. Differential Clock Drive Circuit Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 67 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Typical Application (continued) 10.2.3 Application Curves The ADS5294 is a low-power 80-MSPS 8-Channel ADC. The digital processing block of the ADS5294 integrates several commonly used digital features for improving system performance. The device includes a digital filter module that has built-in decimation filters (with lowpass, highpass and bandpass characteristics). The decimation rate is programmable (by 2, by 4, or by 8). This rate is useful for narrow-band applications, where the filters are used to conveniently improve SNR and knock-off harmonics, while at the same time reducing the output data rate. The device also includes an averaging mode where two channels (or even four channels) are averaged to improve SNR. The below application curves show that about 2 dB SNR improvment can be achieved by either enabling 2X decimation or 2-CH averaging features. 0 0 SNR = 76.1 dBFS SINAD = 75.7 dBFS SFDR = 87 dBc THD =84.7 dBc −10 −20 −30 −30 −40 −40 −50 −50 Amplitude (dB) Amplitude (dB) −20 −60 −70 −80 −60 −70 −80 −90 −90 −100 −100 −110 −110 −120 −120 −130 −130 −140 10 20 Frequency (MHz) 30 40 Fs = 80 MSPS Figure 66. SNR without Decimation Enabled SNR = 78.2 dBFS SINAD = 78.2 dBFS Decimate by 2 Filter Enabled −10 −140 0 5 10 Frequency (MHz) 15 20 Fs = 80 MSPS Figure 67. SNR With Decimation Enabled 0 SNR = 77.9 dBFS SINAD = 77.9 dBFS SFDR = 93.13 dBc THD = −96 dBc 2 Channels averaged −10 −20 −30 −40 Amplitude (dB) −50 −60 −70 −80 −90 −100 −110 −120 −130 −140 0 5 10 15 20 25 Frequency (MHz) 30 35 40 Fs = 80 MSPS Figure 68. SNR With 2-CH Average Enabled 68 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 11 Power Supply Recommendations The device requires three supplies in order to operate properly. These supplies are AVDD and LVDD. All supplies must be driven with low-noise sources to be able to achieve the best performance from the device. When determining the drive current needed to drive each of the supplies of the device, a margin of 50-100% over the typical current might be needed to account for the current consumption across different modes of operation. Please also refer to Reset Timing after power up. 12 Layout 12.1 Layout Guidelines A single ground plane is sufficient to give good performance, provided the analog, digital, and clock sections of the board are cleanly partitioned. See the ADS5294VM Evaluation Module (SLAU355) for placement of components, routing, and grounding. Because the ADS5294 already includes internal decoupling, minimal external decoupling can be used without loss in performance. For example, the ADS5294EVM uses a single 0.1-µF decoupling capacitor for each supply, placed close to the device supply pins. The exposed pad at the bottom of the package is the main path for heat dissipation. Solder the pad to a ground plane on the PCB for best thermal performance. The pad must be connected to the ground plane through the optimum number of vias. See TI’s thermal Web site at www.ti.com/thermal for additional information. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 69 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com 12.2 Layout Example LVDS Length Matching Supporting capacitors & resistors next to pins Figure 69. Layout Recommendations 70 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 13 Device and Documentation Support 13.1 Device Support 13.1.1 Device Nomenclature 13.1.1.1 Definition Of Specifications Analog Bandwidth The analog input frequency at which the power of the fundamental is reduced by 3 dB with respect to the low-frequency value. Aperture Delay The delay in time between the rising edge of the input sampling clock and the actual time at which the sampling occurs. This delay is different across channels. The maximum variation is specified as aperture delay variation (channel-to-channel). Aperture Uncertainty (Jitter) The sample-to-sample variation in aperture delay. Clock Pulse Width and Duty Cycle The duty cycle of a clock signal is the ratio of the time the clock signal remains at a logic high (clock pulse width) to the period of the clock signal. Duty cycle is typically expressed as a percentage. A perfect differential sine-wave clock results in a 50% duty cycle. Maximum Conversion Rate The maximum sampling rate at which specified operation is given. All parametric testing is performed at this sampling rate unless otherwise noted. Minimum Conversion Rate The minimum sampling rate at which the ADC functions. Differential Non-Linearity (DNL) An ideal ADC exhibits code transitions at analog input values spaced exactly 1 LSB apart. The DNL is the deviation of any single step from this ideal value, measured in units of LSBs. Integral Nonlinearity (INL) The INL is the deviation of the ADC transfer function from a best fit line determined by a least squares curve fit of that transfer function, measured in units of LSBs. Gain Error Gain error is the deviation of the ADC actual input full-scale range from its ideal value. The gain error is given as a percentage of the ideal input full-scale range. Gain error has two components: error as a result of reference inaccuracy and error as a result of the channel. Both errors are specified independently as EGREF and EGCHAN. To a first-order approximation, the total gain error is ETOTAL ~ EGREF + EGCHAN. For example, if ETOTAL = ±0.5%, the full-scale input varies from (1 – 0.5 / 100) x FSideal to (1 + 0.5 / 100) × FSideal. Offset Error The offset error is the difference, given in number of LSBs, between the ADC actual average idle channel output code and the ideal average idle channel output code. This quantity is often mapped into millivolts. Temperature Drift The temperature drift coefficient (with respect to gain error and offset error) specifies the change per degree Celsius of the parameter from TMIN to TMAX. Temperature drift is calculated by dividing the maximum deviation of the parameter across the TMIN to TMAX range by the difference TMAX – TMIN. Signal-to-Noise Ratio SNR is the ratio of the power of the fundamental (PS) to the noise floor power (PN), excluding the power at DC and the first nine harmonics. SNR = 10Log10 PS PN (7) SNR is either given in units of dBc (dB to carrier) when the absolute power of the fundamental is used as the reference, or dBFS (dB to full-scale) when the power of the fundamental is extrapolated to the converter full-scale range. Signal-to-Noise and Distortion (SINAD) SINAD is the ratio of the power of the fundamental (PS) to the power of all the other spectral components including noise (PN) and distortion (PD), but excluding DC. SINAD = 10Log10 PS PN + PD (8) Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 71 ADS5294 SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 www.ti.com Device Support (continued) SINAD is either given in units of dBc (dB to carrier) when the absolute power of the fundamental is used as the reference, or dBFS (dB to full-scale) when the power of the fundamental is extrapolated to the converter full-scale range. Effective Number of Bits (ENOB) ENOB is a measure of the converter performance as compared to the theoretical limit based on quantization noise. ENOB = SINAD - 1.76 6.02 (9) Total Harmonic Distortion (THD) THD is the ratio of the power of the fundamental (PS) to the power of the first nine harmonics (PD). THD = 10Log10 PS PN (10) THD is typically given in units of dBc (dB to carrier). Spurious-Free Dynamic Range (SFDR) The ratio of the power of the fundamental to the highest other spectral component (either spur or harmonic). SFDR is typically given in units of dBc (dB to carrier). Two-Tone Intermodulation Distortion IMD3 is the ratio of the power of the fundamental (at frequencies f1 and f2) to the power of the worst spectral component at either frequency 2f1 – f2 or 2f2 – f1. IMD3 is either given in units of dBc (dB to carrier) when the absolute power of the fundamental is used as the reference, or dBFS (dB to full-scale) when the power of the fundamental is extrapolated to the converter full-scale range. DC Power-Supply Rejection Ratio (DC PSRR) DC PSSR is the ratio of the change in offset error to a change in analog supply voltage. The DC PSRR is typically given in units of mV/V. AC Power-Supply Rejection Ratio (AC PSRR) AC PSRR is the measure of rejection of variations in the supply voltage by the ADC. If ΔVSUP is the change in supply voltage and ΔVOUT is the resultant change of the ADC output code (referred to the input), then: DVOUT PSRR = 20Log 10 (Expressed in dBc) DVSUP (11) Voltage Overload Recovery The number of clock cycles taken to recover to less than 1% error after an overload on the analog inputs. Voltage overload recovery is tested by separately applying a sine wave signal with 6dB positive and negative overload. The deviation of the first few samples after the overload (from the expected values) is noted. Common-Mode Rejection Ratio (CMRR) CMRR is the measure of rejection of variation in the analog input common-mode by the ADC. If ΔVCM_IN is the change in the common-mode voltage of the input pins and ΔVOUT is the resulting change of the ADC output code (referred to the input), then: DVOUT CMRR = 20Log10 (Expressed in dBc) DVCM (12) Crosstalk (only for multi-channel ADCs) Crosstalk is a measure of the internal coupling of a signal from an adjacent channel into the channel of interest. Crosstalk is specified separately for coupling from the immediate neighboring channel (near-channel) and for coupling from channel across the package (far-channel). Crosstalk is usually measured by applying a full-scale signal in the adjacent channel. Crosstalk is the ratio of the power of the coupling signal (as measured at the output of the channel of interest) to the power of the signal applied at the adjacent channel input. Crosstalk is typically expressed in dBc. 72 Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 ADS5294 www.ti.com SLAS776E – NOVEMBER 2011 – REVISED APRIL 2018 13.2 Documentation Support 13.2.1 Related Documentation For related documentation, see the following: • Clocking High-Speed Data Converters, SLYT075 • CDCM7005 3.3-V High Performance Clock Synchronizer and Jitter Cleaner, SCAS793 • CDCE72010 16-Bit, 2-MSPS, LVDS Serial Interface, SAR ADC, SLAS490 • LMK04800 Family Low-Noise Clock Jitter Cleaner with Dual Loop PLLs, SNAS489 • ADS5294VM Evaluation Module, SLAU355 13.3 Community Resources The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of Use. TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help solve problems with fellow engineers. Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and contact information for technical support. 13.4 Trademarks E2E is a trademark of Texas Instruments. All other trademarks are the property of their respective owners. 13.5 Electrostatic Discharge Caution These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during storage or handling to prevent electrostatic damage to the MOS gates. 13.6 Glossary SLYZ022 — TI Glossary. This glossary lists and explains terms, acronyms, and definitions. 14 Mechanical, Packaging, and Orderable Information The following pages include mechanical, packaging, and orderable information. This information is the most current data available for the designated devices. This data is subject to change without notice and revision of this document. For browser-based versions of this data sheet, refer to the left-hand navigation. Submit Documentation Feedback Copyright © 2011–2018, Texas Instruments Incorporated Product Folder Links: ADS5294 73 PACKAGE OPTION ADDENDUM www.ti.com 10-Dec-2020 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) Device Marking (3) (4/5) (6) ADS5294IPFP ACTIVE HTQFP PFP 80 96 RoHS & Green NIPDAU Level-3-260C-168 HR -40 to 85 ADS5294 ADS5294IPFPR ACTIVE HTQFP PFP 80 1000 RoHS & Green NIPDAU Level-3-260C-168 HR -40 to 85 ADS5294 ADS5294IPFPT ACTIVE HTQFP PFP 80 250 RoHS & Green NIPDAU Level-3-260C-168 HR -40 to 85 ADS5294 (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of