ADS6144IRHBT

ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 14-BITS, 125/105/80/65 MSPS ADC WITH DDR LVDS/CMOS OUTPUTS • FEATURES 1 • • • • • • • • • • • • Maximum Sample Rate: 125 MSPS 14-Bit Resolution with No Missing Codes 3.5 dB Coarse Gain and up to 6 dB Programmable Fine Gain for SNR/SFDR Trade-Off Parallel CMOS and Double Data Rate (DDR) LVDS Output Options Supports Sine, LVCMOS, LVPECL, LVDS Clock Inputs, and Clock Amplitude Down to 400 mVPP Clock Duty Cycle Stabilizer Internal Reference with Support for External Reference No External Decoupling Required for References Programmable Output Clock Position and Drive Strength to Ease Data Capture 3.3-V Analog and 1.8-V to 3.3-V Digital Supply 32-QFN Package (5 mm × 5 mm) Pin Compatible 12-Bit Family (ADS612X) APPLICATIONS • • • • • • • Radar Systems DESCRIPTION ADS6145/ADS6144/ADS6143/ADS6142 (ADS614X) are a family of 14-bit A/D converters with sampling frequencies up to 125 MSPS. The high performance and low power consumption of the ADS614X are combined in a compact 32 QFN package. An internal high bandwidth sample and hold and a low jitter clock buffer help to achieve high SNR and high SFDR even at high input frequencies. The ADS614X feature coarse and fine gain options to improve SFDR performance at lower full-scale analog input ranges. The digital data outputs are either parallel CMOS or DDR (Double Data Rate) LVDS. Several features exist to ease data capture such as — controls for output clock position and output buffer drive strength, LVDS current, and internal termination programmability. The output interface type, gain, and other functions are programmed using a 3-wire serial interface. Alternatively, some functions are configured using dedicated parallel pins so the device powers up to the desired state. The ADS614X include internal references while eliminating traditional reference pins and associated external decoupling. External reference mode is also supported. Wireless Communications Infrastructure Software Defined Radio Power Amplifier Linearization 802.16d/e Test and Measurement Instrumentation High Definition Video Medical Imaging The ADS614X are specified over the industrial temperature range (–40°C to 85°C). ADS614X Performance Summary SFDR, dBc SINAD, dBFS ADS6145 ADS6144 ADS6143 ADS6142 Fin = 10 MHz (0 dB gain) 90 91 93 95 Fin = 170 MHz (3.5 dB gain) 78 82 83 84 Fin = 10 MHz (0 dB gain) 73.7 74.1 74.5 74.6 Fin = 170 MHz (3.5 dB gain) 68.6 70.5 70.6 71.5 417 374 318 285 Power, mW 1 Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Copyright © 2007–2008, Texas Instruments Incorporated ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. CLKP DRGND DRVDD AGND AVDD ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. CLKOUTP CLOCK GEN CLKM CLKOUTM D0_D1_P D0_D1_M D2_D3_P D2_D3_M D4_D5_P D4_D5_M Digital Encoder and Serializer INP 14-Bit ADC SHA INM D6_D7_P D6_D7_M D8_D9_P D8_D9_M D10_D11_P D10_D11_M VCM Control Interface Reference D12_D13_P D12_D13_M ADS614X PDN SEN SDATA SCLK RESET LVDS MODE ADS61XX FAMILY 2 125 MSPS 105 MSPS 80 MSPS 65 MSPS ADS614X 14 Bits ADS6145 ADS6144 ADS6143 ADS6142 ADS612X 12 Bits ADS6125 ADS6124 ADS6123 ADS6122 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 PACKAGE/ORDERING INFORMATION (1) PRODUCT PACKAGELEAD PACKAGE DESIGNATOR SPECIFIED TEMPERATURE RANGE PACKAGE MARKING ADS6145 QFN-32 (2) RHB –40°C to 85°C AZ6145 ADS6144 QFN-32 (2) RHB –40°C to 85°C AZ6144 ADS6143 ADS6142 (1) (2) QFN-32 (2) RHB QFN-32 (2) RHB –40°C to 85°C –40°C to 85°C AZ6143 AZ6142 ORDERING NUMBER TRANSPORT MEDIA ADS6145IRHBT Tape and Reel, small ADS6145IRHBR Tape and Reel, large ADS6144IRHBT Tape and Reel, small ADS6144IRHBR Tape and Reel, large ADS6143IRHBT Tape and Reel, small ADS6143IRHBR Tape and Reel, large ADS6142IRHBT Tape and Reel, small ADS6142IRHBR Tape and Reel, large For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI website at www.ti.com. For thermal pad size on the package, see the mechanical drawings at the end of this data sheet. θJA = 34 °C/W (0 LFM air flow), θJC = 30 °C/W when used with 2 oz. copper trace and pad soldered directly to a JEDEC standard four layer 3 in × 3 in (7.62 cm × 7.62 cm) PCB. ABSOLUTE MAXIMUM RATINGS (1) VI VALUE UNIT Supply voltage range, AVDD –0.3 to 3.9 V Supply voltage range, DRVDD –0.3 to 3.9 V Voltage between AGND and DRGND –0.3 to 0.3 V Voltage between AVDD to DRVDD –0.3 to 3.3 V –0.3 to 2 V –0.3 to minimum ( 3.6, AVDD + 0.3) V Voltage applied to VCM pin (in external reference mode) Voltage applied to analog input pins, INP and INM Voltage applied to analog input pins, CLKP and CLKM TA Operating free-air temperature range TJ Operating junction temperature range Tstg Storage temperature range (1) –0.3 to (AVDD + 0.3) V –40 to 85 °C 125 °C –65 to 150 °C Stresses beyond 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 affect device reliability. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 3 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 RECOMMENDED OPERATING CONDITIONS over operating free-air temperature range (unless otherwise noted) MIN NOM MAX UNIT 3 3.3 3.6 V 1.65 1.8 to 3.3 3.6 V 3 3.3 3.6 V SUPPLIES AVDD Analog supply voltage DRVDD Output buffer supply voltage (1) CMOS Interface LVDS Interface ANALOG INPUTS Differential input voltage range VIC 2 Input common-mode voltage Vpp 1.5 ± 0.1 Voltage applied on VCM in external reference mode 1.45 1.5 V 1.55 V CLOCK INPUT Input clock sample rate, FS ADS6145 1 125 ADS6144 1 105 ADS6143 1 80 ADS6142 1 Sine wave, ac-coupled Input clock amplitude differential (VCLKP – VCLKM) 65 0.4 LVPECL, ac-coupled 1.5 ± 0.8 LVDS, ac-coupled MSPS Vpp ± 0.35 LVCMOS, ac-coupled 3.3 Input Clock duty cycle 35% 50% 65% DIGITAL OUTPUTS Output buffer drive strength (2) For CLOAD ≤ 5 pF and DRVDD ≥ 2.2 V DEFAULT strength For CLOAD > 5 pF and DRVDD ≥ 2.2 V MAXIMUM strength For DRVDD < 2.2 V MAXIMUM strength CMOS Interface, maximum buffer strength CLOAD Maximum external load capacitance from each output pin to DRGND 10 LVDS Interface, without internal termination 5 LVDS Interface, with internal termination RLOAD Differential load resistance (external) between the LVDS output pairs TA Operating free-air temperature (1) (2) 4 pF 10 Ω 100 -40 85 °C For easy migration to next generation, higher sampling speed devices (> 125 MSPS), use 1.8V DRVDD supply. See Output Buffer Strength Programmability in the application section. Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 ELECTRICAL CHARACTERISTICS Typical values are at 25°C, min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, applies to CMOS and LVDS interfaces, unless otherwise noted. ADS6145 FS = 125 MSPS PARAMETER MIN RESOLUTION TYP ADS6144 FS = 105 MSPS MAX MIN TYP ADS6143 FS = 80 MSPS MAX MIN TYP ADS6142 FS = 65 MSPS MAX MIN TYP UNIT MAX 14 14 14 14 Bits 2 2 2 2 VPP >1 >1 >1 >1 MΩ 7 7 7 7 pF Analog input bandwidth 450 450 450 450 MHz Analog input common-mode current (per input pin of each ADC) 180 151 114 92 µA ANALOG INPUT Differential input voltage range Differential input resistance (dc), see Figure 94 Differential input capacitance, see Figure 95 REFERENCE VOLTAGES VREFB Internal reference bottom voltage 1 1 1 1 V VREFT Internal reference top voltage 2 2 2 2 V ΔVREF Internal reference error (VREFT–VREFB) VCM Common-mode output voltage -20 VCM Output current capability ±5 20 -20 ±5 20 -20 ±5 20 -20 ±5 1.5 1.5 1.5 1.5 4 4 4 4 20 mV V mA DC ACCURACY No missing codes EO Specified Offset error -10 Offset error temperature coefficient ±2 Specified 10 -10 0.05 ±2 Specified 10 -10 0.05 ±2 Specified 10 -10 0.05 ±2 10 0.05 mV mV/°C There are two sources of gain error – internal reference inaccuracy and channel gain error EGREF EGCHAN Gain error due to internal reference inaccuracy alone, (ΔVREF /2) % Gain error of channel alone (1) -1 0.25 1 -1 0.25 1 -1 0.25 1 -1 0.25 1 % FS -1 ±0.3 1 -1 ±0.3 1 -1 ±0.3 1 -1 ±0.3 1 % FS Channel gain error temperature coefficient DNL Differential nonlinearity INL Integral nonlinearity 0.005 0.005 0.005 Δ%/°C 0.005 -0.95 ± 0.6 2 -0.95 ± 0.6 2 -0.95 ± 0.5 2 -0.95 ± 0.5 2 LSB -4.5 ± 2.5 4.5 -4.5 ± 2.5 4.5 -4 ±2 4 -4 ±2 4 LSB POWER SUPPLY IAVDD Analog supply current IDRVDD Digital supply current, CMOS interface, DRVDD = 1.8 V, No load capacitance, Fin= 2 MHz IDRVDD (1) (2) (3) 123 110 94 84 mA 6.1 5.4 4.5 4.0 mA 42 42 42 42 mA (2) Digital supply current, LVDS interface, DRVDD = 3.3 V, with 100-Ω external termination Total power, CMOS, DRVDD = 3.3 V (3) 417 625 374 525 318 440 285 400 mW Global power down 30 60 30 60 30 60 30 60 mW Specified by design and characterization; not tested in production. In CMOS mode, the DRVDD current scales with the sampling frequency and the load capacitance on the output pins (see Figure 87). The maximum DRVDD current depends on the actual load capacitance on the digital output lines. Note that the maximum recommended load capacitance is 10 pF. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 5 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 ELECTRICAL CHARACTERISTICS Typical values are at 25°C, min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, applies to CMOS and LVDS interfaces, unless otherwise noted. PARAMETER TEST CONDITIONS ADS6145 FS = 125 MSPS MIN TYP MAX ADS6144 FS = 105 MSPS MIN TYP MAX ADS6143 FS = 80 MSPS MIN TYP MAX ADS6142 FS = 65 MSPS MIN TYP UNIT MAX DYNAMIC AC CHARACTERISTICS Fin = 10 MHz Fin = 50 MHz 70 Fin = 70 MHz SNR Signal-to-noise ratio, CMOS 0 dB Gain Fin = 50 MHz 70.5 Fin = 70 MHz 71.1 71.8 72.3 74.4 72.7 70.1 70.9 71.4 71.8 69.8 70.7 71.3 71.7 69 69.9 70.4 70.9 74.5 74.4 74.4 73.9 74.9 75 74.4 74.6 72.8 72.9 71.5 71.5 71.9 72.1 0 dB Gain Fin = 230 MHz 3.5 dB Coarse gain 71.2 71.2 71.8 72 70.5 70.5 71.1 71.2 Inputs tied to common-mode 1.05 1.05 1.05 1.05 73.7 74.1 74.5 74.6 72.3 73 69 Fin = 70 MHz 72.6 0 dB Gain 69.5 Fin = 70 MHz 69 0 dB Gain 0 dB Gain Fin = 230 MHz 3.5 dB Coarse gain 11.1 68.7 71 71.1 72.2 68.6 70.5 70.6 71.5 67.3 69 70.2 70.6 67 69 69.9 70.4 74.3 74.3 74.8 74.9 72.7 72.9 69.5 Fin = 10 MHz 76 74.0 70.5 74.3 74.4 73.6 70.6 71.4 72 72.4 70.8 71.1 71.6 71.9 69.4 69.2 71 70.5 69.4 69.4 70.7 70.5 11.7 11.3 70.5 74.4 91 80 83 78 12 11.8 90 84 Submit Documentation Feedback 70 73.5 11.1 0 dB Gain Fin = 230 MHz 3.5 dB Coarse gain 74.1 73.3 Fin = 70 MHz Fin = 170 MHz 3.5 dB Coarse gain 74.1 LSB dBFS Fin = 170 MHz 3.5 dB Coarse gain 0 dB Gain 70 73.2 73.4 Fin = 70 MHz 74.6 dBFS Fin = 170 MHz 3.5 dB Coarse gain Fin = 50 MHz 71.5 dBFS Fin = 170 MHz 3.5 dB Coarse gain Fin = 50 MHz 70.5 71.5 74.3 Fin = 50 MHz 6 71 72.3 Fin = 10 MHz SFDR Spurious free dynamic range 74.4 74.1 74.1 0 dB Gain Fin = 230 MHz 3.5 dB Coarse gain ENOB Effective number of bits 74.7 74.2 72.3 Fin = 50 MHz SINAD Signal-to-noise and distortion ratio LVDS 70 74.6 71 73.9 74.1 0 dB Gain Fin = 10 MHz SINAD Signal-to-noise and distortion ratio CMOS 73.7 dBFS Fin = 170 MHz 3.5 dB Coarse gain Fin = 10 MHz RMS output noise 74.3 73.7 73.3 0 dB Gain Fin = 230 MHz 3.5 dB Coarse gain SNR Signal-to-noise ratio, LVDS 73.9 11.3 93 79 12 Bits 95 89 89 84 84 79 76 80 81 86 82 78 82 83 84 75 77 79 79 76 79 81 82 dBc Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 ELECTRICAL CHARACTERISTICS (continued) Typical values are at 25°C, min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, applies to CMOS and LVDS interfaces, unless otherwise noted. PARAMETER TEST CONDITIONS ADS6145 FS = 125 MSPS MIN Fin = 10 MHz Fin = 50 MHz 73 Fin = 70 MHz THD Total harmonic distortion Fin = 10 MHz 76 Fin = 70 MHz 0 dB Gain 0 dB Gain Fin = 230 MHz 3.5 dB Coarse gain Fin = 10 MHz HD3 Third harmonic distortion Worst spur (other than HD2, HD3) 90 82.5 75 MAX MIN 76 TYP MAX ADS6142 FS = 65 MSPS MIN TYP 91.5 93 88 88 83 83 73.5 79 78 76 80 75 81 79 82 71.5 75.5 76 76 72.5 77.5 78 78.5 96 96 97 98 95 96 76 85 78 79 96 96 92 93 81 83 83 86 82 84 84 87 75 79 80 79 76 81 81 81 90 91 93 95 80 83 84 79 93 89 89 84 76 80 81 82 78 82 83 84 0 dB Gain Fin = 230 MHz 3.5 dB Coarse gain 75 77 79 79 76 79 81 82 Fin = 10 MHz 93 94 96 97 Fin = 50 MHz 92 90 93 96 Fin = 70 MHz 91 90 92 95 Fin = 170 MHz 90 89 89 91 Fin = 170 MHz 3.5 dB Coarse gain 78 79 84 0 dB Gain UNIT MAX dBc Fin = 170 MHz 3.5 dB Coarse gain Fin = 70 MHz TYP 79.5 91 Fin = 50 MHz MIN ADS6143 FS = 80 MSPS dBc Fin = 170 MHz 3.5 dB Coarse gain Fin = 50 MHz MAX 88.5 82 0 dB Gain 0 dB Gain Fin = 230 MHz 3.5 dB Coarse gain HD2 Second harmonic distortion TYP ADS6144 FS = 105 MSPS 79 86 dBc dBc Fin = 230 MHz 90 88 89 90 IMD 2-Tone intermodulation distortion F1 = 185 MHz, F2 = 190 MHz, Each tone at -7 dBFS 83 82 84 88 dBFS Input overload recovery Recovery to within 1% (of final value) for 6-dB overload with sine wave input 1 1 1 1 clock cycles PSRR AC Power supply rejection ratio For 100 mVpp signal on AVDD supply 35 35 35 35 dBc Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 7 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 DIGITAL CHARACTERISTICS (1) The dc specifications refer to the condition where the digital outputs are not switching, but are permanently at a valid logic level 0 or 1, AVDD = 3.3 V PARAMETER TEST CONDITIONS ADS6145/ADS6144 ADS6143/ADS6142 MIN DIGITAL INPUTS PDN, SCLK, SDATA, and SEN TYP MAX UNIT (2) High-level input voltage 2.4 V Low-level input voltage 0.8 V High-level input current 33 µA Low-level input current –33 µA 4 pF High-level output voltage DRVDD V Low-level output voltage 0 V 2 pF High-level output voltage 1375 mV Low-level output voltage 1025 mV 350 mV 1200 mV 2 pF Input capacitance DIGITAL OUTPUTS CMOS INTERFACE, DRVDD = 1.8 to 3.3 V Output capacitance inside the device, from each output to ground Output capacitance DIGITAL OUTPUTS LVDS INTERFACE, DRVDD = 3.3 V, IO = 3.5 mA, RL = 100 Ω (3) |VOD| Output differential voltage VOS Output offset voltage, single-ended Common-mode voltage of OUTP, OUTM Output capacitance Output capacitance inside the device, from either output to ground (1) (2) (3) 8 225 All LVDS and CMOS specifications are characterized, but not tested at production. SCLK and SEN function as digital input pins when they are used for serial interface programming. When used as parallel control pins, analog voltage needs to be applied as per Table 1 & Table 2 IO Refers to the LVDS buffer current setting, RL is the differential load resistance between the LVDS output pair. Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TIMING CHARACTERISTICS – LVDS AND CMOS MODES (1) Typical values are at 25°C, min and max values are across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP clock amplitude, CL = 5 pF (2), IO = 3.5 mA, RL = 100 Ω (3), no internal termination, unless otherwise noted. For timings at lower sampling frequencies, see section Output Timings in the APPLICATION INFORMATION of this data sheet. PARAMETER ta Aperture delay tj Aperture jitter Wake-up time (to valid data) TEST CONDITIONS ADS6145 FS = 125 MSPS ADS6144 FS = 105 MSPS ADS6142 FS = 65 MSPS UNIT MIN TYP MAX MIN TYP MAX MIN TYP MAX MIN TYP MAX 0.7 1.5 2.5 0.7 1.5 2.5 0.7 1.5 2.5 0.7 1.5 2.5 150 From global power down 15 150 50 150 15 50 15 150 50 15 ns fs rms 50 µs 15 50 15 50 15 50 15 50 µs CMOS 100 200 100 200 100 200 100 200 ns LVDS 200 500 200 500 200 500 200 500 ns From standby From output buffer disable ADS6143 FS = 80 MSPS Latency 9 9 9 clock cycles 9 DDR LVDS MODE (4), DRVDD = 3.3 V tsu Data setup time (5) Data valid (6) to zero-cross of CLKOUTP 1.7 2.3 2.5 3.1 3.9 4.5 5.4 6.0 ns th Data hold time (5) Zero-cross of CLKOUTP to data becoming invalid (6) 0.7 1.7 0.7 1.7 0.7 1.7 0.7 1.7 ns tPDI Clock propagation delay Input clock rising edge zero-cross to output clock rising edge zero-cross 4.3 5.8 7.3 4.3 5.8 7.3 4.3 5.8 7.3 4.3 5.8 7.3 LVDS bit clock duty cycle Duty cycle of differential clock, (CLKOUTPCLKOUTM), 10 ≤ Fs ≤ 125 MSPS 40% 47% 55% 40% 47% 55% 40% 47% 55% 40% 47% 55% Data rise time, Data fall time Rise time measured from –50 mV to 50 mV, Fall time measured from 50 mV to –50 mV, 1 ≤ Fs ≤ 125 MSPS 70 100 170 70 100 170 70 100 170 70 100 170 ps Output clock rise time, Output clock fall time Rise time measured from –50 mV to 50 mV, Fall time measured from 50 mV to –50 mV, 1 ≤ Fs ≤ 125 MSPS 70 100 170 70 100 170 70 100 170 70 100 170 ps tr tf tCLKRI SE tCLKFA LL PARALLEL CMOS MODE, DRVDD = 2.5 V to 3.3 V, default output buffer drive strength ns (7) (8) tsu Data setup time (5) Data valid to 50% of CLKOUT rising edge 2.9 4.4 3.6 5.1 5.1 6.6 6.5 8.0 ns th Data hold time (5) 50% of CLKOUT rising edge to data becoming invalid (8) 1.3 2.7 2.1 3.5 3.6 5.0 5.1 6.5 ns (1) (2) (3) (4) (5) (6) (7) (8) Timing parameters are specified by design and characterization and not tested in production. CL is the Effective external single-ended load capacitance between each output pin and ground. IO Refers to the LVDS buffer current setting; RL is the differential load resistance between the LVDS output pair. Measurements are done with a transmission line of 100 Ω characteristic impedance between the device and the load. Setup and hold time specifications take into account the effect of jitter on the output data and clock. Data valid refers to a logic high of +100 mV and logic low of –100 mV. For DRVDD < 2.2 V, it is recommended to use an external clock for data capture and NOT the device output clock signal (CLKOUT). See Parallel CMOS interface in the application section. Data valid refers to a logic high of 2 V (1.7 V) and logic low of 0.8 V (0.7 V) for DRVDD = 3.3 V (2.5 V). Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 9 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TIMING CHARACTERISTICS – LVDS AND CMOS MODES (continued) For timings at lower sampling frequencies, see section Output Timings in the APPLICATION INFORMATION of this data sheet. PARAMETER tPDI tr tf tCLKRI SE tCLKFA LL 10 TEST CONDITIONS ADS6145 FS = 125 MSPS ADS6144 FS = 105 MSPS ADS6143 FS = 80 MSPS ADS6142 FS = 65 MSPS UNIT MIN TYP MAX MIN TYP MAX MIN TYP MAX MIN TYP MAX 5 6.5 7.9 5 6.5 7.9 5 6.5 7.9 5 6.5 7.9 Clock propagation delay Input clock rising edge zero-cross to 50% of CLKOUT rising edge Output clock duty cycle Duty cycle of output clock (CLKOUT), 10 ≤ Fs ≤ 125 MSPS 45% 50% 55% 45% 50% 55% 45% 50% 55% 45% 50% 55% Data rise time, Data fall time Rise time measured from 20% to 80% of DRVDD, Fall time measured from 80% to 20% of DRVDD, 1 ≤ Fs ≤ 125 MSPS 0.8 1.5 2.4 0.8 1.5 2.4 0.8 1.5 2.4 0.8 1.5 2.4 ns Output clock rise time, Output clock fall time Rise time measured from 20% to 80% of DRVDD, Fall time measured from 80% to 20% of DRVDD, 1 ≤ Fs ≤ 125 MSPS 0.8 1.5 2.4 0.8 1.5 2.4 0.8 1.5 2.4 0.8 1.5 2.4 ns Submit Documentation Feedback ns Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 N+4 N+3 N+2 N+12 N+11 N+10 N+1 Sample N N+9 Input Signal ta CLKP Input Clock CLKM CLKOUTM CLKOUTP tsu DDR LVDS Output Data DXP, DXM O O E E – Even Bits D0,D2,D4,D6,D8,D10,D12 O – Odd Bits D1,D3,D5,D7,D9,D11,D13 E O O E N–8 N–9 O E N–7 tPDI th 9 Clock Cycles E O N–6 O E N–5 E O E N N–1 O O E E N+2 N+1 tPDI CLKOUT tsu Parallel CMOS 9 Clock Cycles Output Data D0–D13 N–8 N–9 N–7 th N–6 N–5 N–1 N N+1 N+2 Figure 1. Latency Input Clock CLKM CLKM Input Clock CLKP CLKP tPDI tPDI Output Clock CLKOUTM Output Clock CLKOUTP CLKOUT tsu th tsu th th tsu Output Data Pair (1) (2) Dn Dn_Dn+1_P, Dn_Dn+1_M Dn (1) Dn+1 (2) Output Data Dn Dn (1) – Bits D0, D2, D4, D6, D8, D10, D12 Dn+1 – Bits D1, D3, D5, D7, D9, D11, D13 Figure 2. LVDS Mode Timing Copyright © 2007–2008, Texas Instruments Incorporated (1) Dn – Bits D0–D13 Figure 3. CMOS Mode Timing Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 11 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 DEVICE PROGRAMMING MODES The ADS614X have several features that can be easily configured using either parallel interface control or serial interface programming. USING SERIAL INTERFACE PROGRAMMING ONLY To program using the serial interface, the internal registers must first be reset to their default values, and the RESET pin must be kept low. In this mode, SEN, SDATA, and SCLK function as serial interface pins and are used to access the internal registers of the ADC. The registers are reset either by applying a pulse on the RESET pin or by a high setting on the bit (D4 in register 0x00). The Serial Interface section describes register programming and register reset in more detail. USING PARALLEL INTERFACE CONTROL ONLY To control the device using the parallel interface, keep RESET tied high (AVDD). Now SEN, SCLK, SDATA, and PDN function as parallel interface control pins. These pins can be used to directly control certain modes of the ADC by connecting them to the correct voltage levels (as described in Table 1 to Table 3). There is no need to apply a reset pulse. Frequently used functions are controlled in this mode — standby, selection between LVDS/CMOS output format, internal/external reference, and 2s complement/straight binary output format. AVDD (5/8) AVDD 3R (5/8) AVDD GND 2R AVDD (3/8) AVDD (3/8) AVDD 3R To Parallel Pin (SCLK, SDATA, SEN) GND Figure 4. Simple Scheme to Configure Parallel Pins DESCRIPTION OF PARALLEL PINS Table 1. SCLK (Analog Control Pin) SCLK DESCRIPTION 0 Internal reference and 0 dB gain (full-scale = 2 VPP) (3/8) AVDD External reference and 0 dB gain (full-scale = 2 VPP) (5/8) AVDD External reference and 3.5 dB coarse gain (full-scale = 1.34 VPP) AVDD Internal reference and 3.5 dB coarse gain (full-scale = 1.34 VPP) Table 2. SEN (Analog Control Pin) SEN 0 2s Complement format and DDR LVDS interface (3/8) AVDD Straight binary format and DDR LVDS interface (5/8) AVDD Straight binary and parallel CMOS interface AVDD 12 DESCRIPTION 2s Complement format and parallel CMOS interface Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Table 3. SDATA, PDN (Digital Control Pins) SDATA PDN DESCRIPTION Low Low Low High (AVDD) Normal operation High (AVDD) Low High (AVDD) High (AVDD) Standby - only the ADC is powered down Output buffers are powered down, fast wake-up time Global power down. ADC, internal reference, and output buffers are powered down, slow wake-up time SERIAL INTERFACE The ADC has a set of internal registers, which can be accessed through the serial interface formed by pins SEN (Serial interface Enable), SCLK (Serial Interface Clock), SDATA (Serial Interface Data) and RESET. After device power-up, the internal registers must be reset to their default values by applying a high-going pulse on RESET (of width greater than 10 ns). Serial shift of bits into the device is enabled when SEN is low. Serial data SDATA is latched at every falling edge of SCLK when SEN is active (low). The serial data is loaded into the register at every 16th SCLK falling edge when SEN is low. If the word length exceeds a multiple of 16 bits, the excess bits are ignored. Data is loaded in multiples of 16-bit words within a single active SEN pulse. The first 5 bits form the register address and the remaining 11 bits form the register data. The interface can work with a SCLK frequency from 20 MHz down to very low speeds (a few hertz) and also with a non-50% SCLK duty cycle. REGISTER ADDRESS SDATA A4 A3 A2 A1 REGISTER DATA A0 D10 D9 D8 D7 D6 D5 D4 tDSU tSCLK D3 D2 D1 D0 tDH SCLK tSLOADH SEN tSLOADS RESET Figure 5. Serial Interface Timing Diagram REGISTER INITIALIZATION After power-up, the internal registers must be reset to their default values. This is done in one of two ways: 1. Either through a hardware reset by applying a high-going pulse on the RESET pin (width greater than 10 ns) as shown in Figure 5. OR 2. By applying a software reset. Using the serial interface, set the bit (D4 in register 0x00) to high. This initializes the internal registers to their default values and then self-resets the bit to low. In this case the RESET pin is kept low. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 13 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 SERIAL INTERFACE TIMING Typical values at 25°C, min and max values across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = DRVDD = 3.3 V (unless otherwise noted) MIN TYP MAX UNIT > DC 20 MHz fSCLK SCLK Frequency = 1/tSCLK tSLOADS SEN to SCLK Setup time 25 ns tSLOADH SCLK to SEN Hold time 25 ns tDSU SDATA Setup time 25 ns tDH SDATA Hold time 25 ns RESET TIMING Typical values at 25°C, min and max values across the full temperature range TMIN = –40°C to TMAX = 85°C, AVDD = DRVDD = 3.3 V (unless otherwise noted) PARAMETER TEST CONDITIONS MIN t1 Power-on delay Delay from power-up of AVDD and DRVDD to RESET pulse active t2 Reset pulse width t3 tPO TYP MAX UNIT 5 ms Pulse width of active RESET signal 10 ns Register write delay Delay from RESET disable to SEN active 25 Power-up time Delay from power-up of AVDD and DRVDD to output stable ns 6.5 ms Power Supply AVDD, DRVDD t1 RESET t2 t3 SEN NOTE: A high-going pulse on the RESET pin is required in serial interface mode in the case of initialization through a hardware reset. For parallel interface operation, RESET has to be tied permanently HIGH. Figure 6. Reset Timing Diagram 14 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 SERIAL REGISTER MAP Table 4 gives a summary of all the modes that can be programmed through the serial interface. Table 4. Summary of Functions Supported by Serial Interface (1) (2) REGISTER ADDRESS IN HEX REGISTER FUNCTIONS A4 - A0 D10 D9 D8 00 Output buffers powered down Coarse gain LVDS or CMOS Output interface 0 0 Internal or external Reference 04 Output data position control Output clock edge control Output clock position control 0 0 09 Bit-wise or Byte-wise control 0 0 0 0 0A 2s Complemen t or straight binary 0 0 D6 D5 D4 D3 D2 D1 D0 Software reset 0 Output clock buffer powered down 0 ADC Power down 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Custom pattern lower 9 bits 0B Fine gain 0 to 6dB 0C (1) (2) D7 0E 0 0F 0 0 0 0 LVDS Termination LVDS Internal termination control for output data and clock 0 0 CMOS output buffer drive strength control Custom pattern upper 5 bits LVDS Current control 0 0 LVDS current double 0 0 The unused bits in each register (shown by blank cells in above table) must be programmed as ‘0’. Multiple functions in a register can be programmed in a single write operation. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 15 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 DESCRIPTION OF SERIAL REGISTERS Each register function is explained in detail. Table 5. A4–A0 (hex) 00 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Output buffers powered down Coarse gain LVDS or CMOS Output interface 0 0 Internal or external reference Software reset 0 Output clock buffer powered down 0 ADC Power down D0 0 Normal operation 1 Device enters standby mode where only ADC is powered down. D2 Power down modes 0 Output clock is active (on CLKOUT pin) 1 Output clock buffer is powered down and becomes three-stated. Data outputs are unaffected. D4 1 Software reset applied - resets all internal registers and the bit self-clears to 0. D5 Reference selection 0 Internal reference enabled 1 External reference enabled D8 Output Interface selection 0 Parallel CMOS interface 1 DDR LVDS Interface D9 Gain programming 0 0 dB Coarse gain 1 3.5 dB Coarse gain D10 16 Power down modes Power down modes 0 Output data and clock buffers enabled 1 Output data and clock buffers disabled Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Table 6. A4–A0 (hex) 04 D8 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Output data position control Output Clock edge control Output clock position control 0 0 0 0 0 0 0 0 Output clock position control 0 Default output clock position after reset. The setup/hold timings for this clock position are specified in the timing specifications table. 1 Output clock shifted (delayed) by 400 ps D9 0 Use rising edge to capture data 1 Use falling edge to capture data D10 0 Default position (after reset) 1 Data transition delayed by half clock cycle with respect to default position Table 7. A4–A0 (hex) 09 D10 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Bit-wise or Byte-wise control 0 0 0 0 0 0 0 0 0 0 Bit-wise or byte-wise selection (DDR LVDS mode only) 0 Bit-wise sequence - Even data bits (D0, D2, D4,..D12) are output at the rising edge of CLKOUTP and odd data bits (D1, D3, D5,..D13) at the falling edge of CLKOUTP 1 Byte-wise sequence - Lower 7 data bits (D0-D7) are output at the rising edge of CLKOUTP and upper 7 data bits (D8-D13) at the falling edge of CLKOUTP Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 17 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Table 8. A4–A0 (hex) 0A D7-D5 D10 D9 D8 2s Complement or straight binary 0 0 D7 D6 D5 D4 D3 D2 D1 D0 0 0 0 0 0 Test patterns 000 Normal operation - = ADC output 001 All zeros - = 0x0000 010 All ones - = 0x3FFF 011 Toggle pattern - toggles between 0x2AAA and 0x1555 100 Digital ramp - increments from 0x0000 to 0x3FFF by one code every cycle 101 Custom pattern - = contents of CUSTOM PATTERN registers 110 Unused 111 Unused D10 0 2s Complement 1 Straight binary Table 9. A4–A0 (hex) D10 D9 D8 0B D7 D6 D5 D4 D3 D2 Lower 9 bits of custom pattern D1 D0 0 0 D1 D0 Table 10. A4–A0 (hex) D10 0C 18 D9 D8 Fine gain 0 to 6dB D7 D6 D5 0 0 0 D4 - Specifies lower 9 bits of custom pattern Reg 0C D4-D0 - Specifies upper 5 bits of custom pattern D10-D8 Gain programming 0 dB Gain 001 1 dB Gain 010 2 dB Gain 011 3 dB Gain 100 4 dB Gain 101 5 dB Gain 110 6 dB Gain 111 Unused Submit Documentation Feedback D2 Upper 5 bits of custom pattern Reg 0B D10-D2 000 D3 Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Table 11. A4–A0 (hex) D10 0E 0 D1-D0 D0 D9 D8 D7 D4 D2 LVDS Current control D1 D0 LVDS Current double LVDS Data buffer current control 1 2x LVDS Current set by LVDS Clock buffer current control 0 Default current, set by 1 2x LVDS Current set by LVDS current programming 00 3.5 mA 01 2.5 mA 10 4.5 mA 11 1.75 mA D9-D4 LVDS internal termination D9-D7 Internal termination for LVDS output data bits 000 No internal termination 001 300 Ω 010 185 Ω 011 115 Ω 100 150 Ω 101 100 Ω 110 80 Ω 111 65 Ω D6-D4 D3 LVDS current programming Default current, set by D3-D2 D5 LVDS Internal termination control for output data and clock 0 D1 D6 Internal termination for LVDS output clock 000 No internal termination 001 300 Ω 010 185 Ω 011 115 Ω 100 150 Ω 101 100 Ω 110 80 Ω 111 65 Ω Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 19 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Table 12. A4–A0 (hex) D10 D9 D8 0F 0 0 0 D7-D4 D7 D6 D5 D4 CMOS Output buffer drive strength control D3 D2 D1 D0 0 0 0 0 Output buffer drive strength controls 0101 WEAKER than default drive 0000 DEFAULT drive strength 1111 STRONGER than default drive strength (recommended for load capacitances > 5 pF) 1010 MAXIMUM drive strength (recommended for load capacitances > 5 pF) Other Do not use combinations 20 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 PIN CONFIGURATION (CMOS MODE) DRVDD 1 25 OVR 26 CLKOUT 27 D8 28 D9 29 D10 30 D11 31 D12 32 D13 RHB PACKAGE (TOP VIEW) 24 D7 Pad Connected To DRGND RESET 2 23 D6 CLKP 7 18 D1 CLKM 8 17 D0 PDN 16 19 D2 AVDD 15 AGND 6 VCM 14 20 D3 AVDD 13 SEN 5 AGND 12 21 D4 INM 11 SDATA 4 INP 10 22 D5 AGND 9 SCLK 3 Figure 7. CMOS Mode Pinout PIN ASSIGNMENTS – CMOS Mode PIN NAME PIN TYPE DESCRIPTION PIN NUMBER NUMBER OF PINS AVDD Analog power supply I 13, 15 2 AGND Analog ground I 6, 9, 12 3 CLKP, CLKM Differential clock inputs I 7, 8 2 INP, INM Differential analog inputs I 10, 11 2 VCM Internal reference mode – common-mode voltage output. External reference mode – reference input. The voltage forced on this pin sets the internal references. I/O 14 1 RESET Serial interface RESET input. When using serial interface mode, the user MUST initialize the internal registers through a hardware RESET by applying a high-going pulse on this pin, or by using the software reset option. See the SERIAL INTERFACE section. In parallel interface mode, the user has to tie the RESET pin permanently HIGH. (SCLK, SDATA, and SEN are used as parallel pin controls in this mode.) The pin has an internal 100-kΩ pull-down resistor. I 2 1 SCLK This pin functions as the serial interface clock input when RESET is low. When RESET is tied high, it controls coarse gain and internal/external reference selection. Tie SCLK low for internal reference and 0 dB gain and high for internal reference and 3.5 dB gain. See Table 1. The pin has an internal 100-kΩ pull-down resistor. I 3 1 I 4 1 SEN This pin functions as the serial interface enable input when RESET is low. When RESET is high, it controls output interface type and data formats. See Table 2 for detailed information. The pin has an internal 100-kΩ pull-up resistor to DRVDD. I 5 1 PDN Global power-down control pin I 16 1 This pin functions as the serial interface data input when RESET is low. It controls various power down modes along with the PDN pin when RESET is tied high. SDATA See Table 3 for detailed information. The pin has an internal 100-kΩ pull-down resistor. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 21 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 PIN ASSIGNMENTS – CMOS Mode (continued) PIN NAME DESCRIPTION PIN TYPE PIN NUMBER NUMBER OF PINS CLKOUT CMOS Output clock O 26 1 D0 CMOS Output data D0 O 17 1 D1 CMOS Output data D1 O 18 1 D2 CMOS Output data D2 O 19 1 D3 CMOS Output data D3 O 20 1 D4 CMOS Output data D4 O 21 1 D5 CMOS Output data D5 O 22 1 D6 CMOS Output data D6 O 23 1 D7 CMOS Output data D7 O 24 1 D8 CMOS Output data D8 O 27 1 D9 CMOS Output data D9 O 28 1 D10 CMOS Output data D10 O 29 1 D11 CMOS Output data D11 O 30 1 D12 CMOS Output data D12 O 31 1 D13 CMOS Output data D13 O 32 1 OVR Indicates overvoltage on analog inputs (for differential input greater than full-scale), CMOS level O 25 1 DRVDD Digital supply I 1 1 DRGND Digital ground. Connect the pad to the ground plane. See Board Design Considerations in the application information section. I PAD 1 22 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 PIN CONFIGURATION (LVDS MODE) DRVDD 1 25 CLKOUTM 26 CLKOUTP 27 D8_D9_M 28 D8_D9_P 29 D10_D11_M 30 D10_D11_P 31 D12_D13_M 32 D12_D13_P RHB PACKAGE (TOP VIEW) 24 D6_D7_P Pad Connected To DRGND RESET 2 23 D6_D7_M CLKP 7 18 D0_D1_P CLKM 8 17 D0_D1_M PDN 16 19 D2_D3_M AVDD 15 AGND 6 VCM 14 20 D2_D3_P AVDD 13 SEN 5 AGND 12 21 D4_D5_M INM 11 SDATA 4 INP 10 22 D4_D5_P AGND 9 SCLK 3 Figure 8. LVDS Mode Pinout PIN ASSIGNMENTS – LVDS Mode PIN NAME DESCRIPTION PIN TYPE PIN NUMBER NUMBER OF PINS AVDD Analog power supply I 13, 15 2 AGND Analog ground I 6, 9, 12 3 CLKP, CLKM Differential clock inputs I 7, 8 2 INP, INM Differential analog inputs I 10, 11 2 VCM Internal reference mode – common-mode voltage output. External reference mode – reference input. The voltage forced on this pin sets the internal references. I/O 14 1 RESET Serial interface RESET input. When using serial interface mode, the user MUST initialize the internal registers through a hardware RESET by applying a high-going pulse on this pin or by using the software reset option. See the SERIAL INTERFACE section. In parallel interface mode, the user has to tie the RESET pin permanently HIGH. (SCLK, SDATA, and SEN are used as parallel pin controls in this mode.) The pin has an internal 100-kΩ pull-down resistor. I 2 1 SCLK This pin functions as the serial interface clock input when RESET is low. When RESET is tied high, it controls coarse gain and internal/external reference selection. Tie SCLK low for internal reference and 0 dB gain and high for internal reference and 3.5 dB gain. See Table 1. The pin has an internal 100-kΩ pull-down resistor. I 3 1 I 4 1 This pin functions as the serial interface data input when RESET is low. It controls various power down modes along with the PDN pin when RESET is tied high. SDATA See Table 3 for detailed information. The pin has an internal 100 kΩ pull-down resistor. SEN The pin functions as the serial interface enable input when RESET is low. When RESET is high, it controls output interface type and data formats. See Table 2 for detailed information. The pin has an internal 100-kΩ pull-up resistor to DRVDD. I 5 1 PDN Global power-down control pin I 16 1 Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 23 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 PIN ASSIGNMENTS – LVDS Mode (continued) PIN NAME DESCRIPTION PIN TYPE PIN NUMBER NUMBER OF PINS CLKOUTP Differential output clock, true O 26 1 CLKOUTM Differential output clock, complement O 25 1 D0_D1_P Differential output data D0 and D1 multiplexed, true O 18 1 D0_D1_M Differential output data D0 and D1 multiplexed, complement. O 17 1 D2_D3_P Differential output data D2 and D3 multiplexed, true O 20 1 D2_D3_M Differential output data D2 and D3 multiplexed, complement O 19 1 D4_D5_P Differential output data D4 and D5 multiplexed, true O 22 1 D4_D5_M Differential output data D4 and D5 multiplexed, complement O 21 1 D6_D7_P Differential output data D6 and D7 multiplexed, true O 24 1 D6_D7_M Differential output data D6 and D7 multiplexed, complement O 23 1 D8_D9_P Differential output data D8 and D9 multiplexed, true O 28 1 D8_D9_M Differential output data D8 and D9 multiplexed, complement O 27 1 D10_D11_P Differential output data D10 and D11 multiplexed, true O 30 1 D10_D11_M Differential output data D10 and D11 multiplexed, complement O 29 1 D12_D13_P Differential output data D12 and D13 multiplexed, true O 32 1 D12_D13_M Differential output data D12 and D13 multiplexed, complement O 31 1 DRVDD Digital supply I 1 1 DRGND Digital ground. Connect the pad to the ground plane. See Board Design Considerations in application information section. I PAD 1 24 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6145 (FS= 125 MSPS) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) FFT for 20 MHz INPUT SIGNAL FFT for 70 MHz INPUT SIGNAL 0 0 SFDR = 91.77 dBc SINAD = 73.99 dBFS SNR = 74.2 dBFS THD = 87.79 dBc −20 −40 Amplitude − dB Amplitude − dB −40 −60 −80 −100 −60 −80 −100 −120 −120 −140 −140 −160 −160 0 10 20 30 40 50 60 f − Frequency − MHz 0 10 20 40 50 60 G001 G002 Figure 9. Figure 10. FFT for 230 MHz INPUT SIGNAL INTERMODULATION DISTORTION (IMD) vs FREQUENCY 0 SFDR = 74.2 dBc SINAD = 67.2 dBFS SNR = 69.9 dBFS THD = 71.4 dBc −20 fIN1 = 190 MHz, –7 dBFS fIN2 = 185 MHz, –7 dBFS 2-Tone IMD = –83.5 dBFS SFDR = –81.3 dBFS −20 −40 Amplitude − dB −40 −60 −80 −100 −60 −80 −100 −120 −120 −140 −140 −160 −160 0 10 20 30 40 50 f − Frequency − MHz 60 0 10 20 G003 40 50 60 G004 Figure 12. SFDR vs INPUT FREQUENCY SNR vs INPUT FREQUENCY 76 88 74 84 72 SNR − dBFS 92 80 Gain = 3.5 dB 76 Gain = 0 dB 72 30 f − Frequency − MHz Figure 11. SFDR − dBc 30 f − Frequency − MHz 0 Amplitude − dB SFDR = 84.1 dBc SINAD = 72.88 dBFS SNR = 73.54 dBFS THD = 82.61 dBc −20 Gain = 0 dB 70 Gain = 3.5 dB 68 66 68 64 64 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G005 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz Figure 13. Copyright © 2007–2008, Texas Instruments Incorporated G006 Figure 14. Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 25 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6145 (FS= 125 MSPS) (continued) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) SFDR vs INPUT FREQUENCY (LVDS interface) SNR vs INPUT FREQUENCY (LVDS interface) 92 76 88 74 Gain = 3.5 dB 80 76 Gain = 0 dB 70 Gain = 3.5 dB 68 72 66 68 64 64 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G007 Figure 15. SFDR vs INPUT FREQUENCY ACROSS GAINS SINAD vs INPUT FREQUENCY ACROSS GAINS 95 76 0 dB Input adjusted to get −1dBFS input SINAD − dBFS 5 dB 6 dB 80 4 dB 75 0 dB 70 1 dB 2 dB 72 3 dB 85 SFDR − dBc Input adjusted to get −1dBFS input 74 90 70 68 66 4 dB 64 1 dB 2 dB 65 3 dB 60 0 100 200 300 400 fIN − Input Frequency − MHz 500 0 100 200 G009 PERFORMANCE vs AVDD 77 94 SFDR 80 74 SNR 78 73 76 72 74 71 3.3 3.4 AVDD − Supply Voltage − V 75 3.5 SNR SFDR − dBc 75 3.2 76 fIN = 10.1 MHz AVDD = 3.3 V 76 SNR − dBFS SFDR − dBc PERFORMANCE vs DRVDD 82 3.1 92 74 90 73 SFDR 88 86 1.8 70 3.6 G011 72 2.0 2.2 2.4 2.6 Submit Documentation Feedback 2.8 3.0 DRVDD − Supply Voltage − V Figure 19. 26 500 G010 96 78 84 400 Figure 18. 88 fIN = 70.1 MHz DRVDD = 3.3 V 300 fIN − Input Frequency − MHz Figure 17. 72 3.0 6 dB 5 dB 62 60 86 G008 Figure 16. SNR − dBFS SFDR − dBc Gain = 0 dB 72 SNR − dBFS 84 3.2 3.4 71 3.6 G012 Figure 20. Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6145 (FS= 125 MSPS) (continued) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) PERFORMANCE vs TEMPERATURE PERFORMANCE vs INPUT AMPLITUDE 77 110 SFDR 100 85 88 SNR − dBFS 76 75 SNR 74 84 73 72 80 80 75 SNR (dBFS) 70 70 60 65 SFDR (dBc) 50 60 0 20 40 60 30 −60 80 T − Temperature − °C 55 fIN = 20.1 MHz −50 −40 −30 PERFORMANCE vs CLOCK AMPLITUDE fIN = 20.1 MHz 91 77 84 76 82 75 SNR 90 74 89 88 72 87 73 2.0 2.5 71 fIN = 10.1 MHz 72 3.0 Input Clock Amplitude − VPP 86 70 30 35 40 45 50 55 60 65 70 Input Clock Duty Cycle − % G015 Figure 23. G016 Figure 24. OUTPUT NOISE HISTOGRAM (inputs tied to common-mode) PERFORMANCE IN EXTERNAL REFERENCE MODE 40 93 78 fIN = 20.1 MHz External Reference Mode RMS (LSB) = 1.1 35 91 SFDR − dBc 30 Occurence − % 73 SNR 74 78 1.5 75 SFDR SFDR − dBc 86 1.0 76 78 SNR − dBFS SFDR − dBc PERFORMANCE vs INPUT CLOCK DUTY CYCLE 79 SFDR 76 0.5 G014 92 80 80 50 0 Figure 22. 92 88 −10 Input Amplitude − dBFS G013 Figure 21. 90 −20 SNR − dBFS −20 90 40 fIN = 10.1 MHz 82 −40 SFDR (dBFS) 25 20 15 76 89 74 SNR 87 72 SNR − dBFS 86 SFDR − dBc, dBFS 90 SFDR − dBc 90 SNR − dBFS 92 SFDR 10 85 70 5 0 83 1.30 8206 8207 8208 8209 8210 8211 8212 8213 8214 8215 Output Code G017 1.35 1.40 1.45 1.55 1.60 1.65 68 1.70 VVCM − VCM Voltage − V Figure 25. Copyright © 2007–2008, Texas Instruments Incorporated 1.50 G018 Figure 26. Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 27 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6144 (FS= 105 MSPS) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) FFT for 20 MHz INPUT SIGNAL FFT for 80 MHz INPUT SIGNAL 0 0 SFDR = 88.6 dBc SINAD = 74 dBFS SNR = 74.3 dBFS THD = 87.4 dBc −20 −40 Amplitude − dB Amplitude − dB −40 −60 −80 −100 −60 −80 −100 −120 −120 −140 −140 −160 −160 0 10 20 30 40 50 f − Frequency − MHz 0 10 20 30 40 50 f − Frequency − MHz G019 G020 Figure 27. Figure 28. FFT for 230 MHz INPUT SIGNAL INTERMODULATION DISTORTION (IMD) vs FREQUENCY 0 0 SFDR = 74.9 dBc SINAD = 66.5 dBFS SNR = 67.9 dBFS THD = 73.3 dBc −20 fIN1 = 190 MHz, –7 dBFS fIN2 = 185 MHz, –7 dBFS 2-Tone IMD = –82.3 dBFS SFDR = –87.5 dBFS −20 −40 Amplitude − dB −40 Amplitude − dB SFDR = 84.6 dBc SINAD = 73.1 dBFS SNR = 73.7 dBFS THD = 82.7 dBc −20 −60 −80 −100 −60 −80 −100 −120 −120 −140 −140 −160 −160 0 10 20 30 40 f − Frequency − MHz 50 0 10 20 30 40 f − Frequency − MHz G021 Figure 29. 50 G022 Figure 30. SFDR vs INPUT FREQUENCY SNR vs INPUT FREQUENCY 96 76 92 74 72 84 SNR − dBFS SFDR − dBc 88 Gain = 3.5 dB 80 76 Gain = 0 dB 72 Gain = 0 dB 70 Gain = 3.5 dB 68 66 68 64 64 60 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G023 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz Figure 31. 28 Submit Documentation Feedback G024 Figure 32. Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6144 (FS= 105 MSPS) (continued) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) SFDR vs INPUT FREQUENCY (LVDS interface) SNR vs INPUT FREQUENCY (LVDS interface) 96 76 92 74 88 SNR − dBFS SFDR − dBc Gain = 0 dB 72 84 Gain = 3.5 dB 80 76 Gain = 0 dB 72 70 Gain = 3.5 dB 68 66 68 64 64 60 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G025 Figure 33. SFDR vs INPUT FREQUENCY ACROSS GAINS SINAD vs INPUT FREQUENCY ACROSS GAINS 95 76 Input adjusted to get −1dBFS input 80 0 dB 75 2 dB 72 4 dB 1 dB 68 66 70 1 dB 4 dB 64 2 dB 65 60 60 0 100 200 300 400 500 fIN − Input Frequency − MHz 0 100 200 G027 PERFORMANCE vs AVDD fIN = 70.1 MHz DRVDD = 3.3 V 86 77 SFDR 84 76 82 75 SNR 80 74 78 73 AVDD − Supply Voltage − V 3.5 77 fIN = 10.1 MHz AVDD = 3.3 V 76 SNR 98 SFDR − dBc 78 100 SNR − dBFS 88 3.4 96 G029 74 SFDR 94 73 92 72 90 71 88 1.8 72 3.6 75 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 70 3.6 DRVDD − Supply Voltage − V Figure 37. Copyright © 2007–2008, Texas Instruments Incorporated G028 PERFORMANCE vs DRVDD 79 3.3 500 102 80 3.2 400 Figure 36. 92 3.1 300 fIN − Input Frequency − MHz Figure 35. SFDR − dBc 6 dB 5 dB 62 3 dB 76 3.0 3 dB 70 SNR − dBFS SFDR − dBc 5 dB SINAD − dBFS 6 dB 85 Input adjusted to get −1dBFS input 0 dB 74 90 90 G026 Figure 34. G030 Figure 38. Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 29 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6144 (FS= 105 MSPS) (continued) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) PERFORMANCE vs TEMPERATURE PERFORMANCE vs INPUT AMPLITUDE 93 77 120 76 100 80 75 SNR 87 74 85 SFDR (dBFS) 78 SNR (dBFS) 80 60 76 74 SFDR (dBc) 73 40 72 72 20 −60 fIN = 10.1 MHz 0 20 40 60 80 T − Temperature − °C −50 −40 −30 PERFORMANCE vs CLOCK AMPLITUDE 88 96 79 94 78 92 86 77 84 76 82 75 SNR 78 1.5 2.0 2.5 SNR − dBFS SFDR − dBc SFDR SFDR − dBc fIN = 20.1 MHz 1.0 79 fIN = 10.1 MHz 78 SFDR 77 90 76 88 75 SNR 86 74 74 84 73 73 82 72 72 3.0 80 Input Clock Amplitude − VPP 71 30 35 40 45 50 55 60 65 70 Input Clock Duty Cycle − % G033 Figure 41. G034 Figure 42. OUTPUT NOISE HISTOGRAM WITH INPUTS TIED TO COMMON-MODE PERFORMANCE IN EXTERNAL REFERENCE MODE 40 96 78 fIN = 20.1 MHz External Reference Mode RMS (LSB) = 1.049 35 94 SFDR − dBc 30 Occurence − % G032 PERFORMANCE vs INPUT CLOCK DUTY CYCLE 80 76 0.5 70 0 Figure 40. 92 80 −10 Input Amplitude − dBFS G031 Figure 39. 90 −20 SNR − dBFS −20 fIN = 20.1 MHz 25 20 15 76 SNR 92 74 90 72 SNR − dBFS 83 −40 SNR − dBFS 89 SNR − dBFS SFDR − dBc 91 SFDR − dBc, dBFS SFDR SFDR 10 88 70 5 0 86 1.30 8206 8207 8208 8209 8210 8211 8212 8213 8214 8215 Output Code G035 1.35 1.40 1.45 Submit Documentation Feedback 1.55 VVCM − VCM Voltage − V Figure 43. 30 1.50 1.60 1.65 68 1.70 G036 Figure 44. Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6143 (FS= 80 MSPS) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) FFT for 20 MHz INPUT SIGNAL FFT for 70 MHz INPUT SIGNAL 0 0 SFDR = 89.8 dBc SINAD = 74.5 dBFS SNR = 74.8 dBFS THD = 87 dBc −20 −40 Amplitude − dB Amplitude − dB −40 −60 −80 −100 −60 −80 −100 −120 −120 −140 −140 −160 −160 0 10 20 30 f − Frequency − MHz 40 0 10 20 G037 40 G038 Figure 45. Figure 46. FFT for 230 MHz INPUT SIGNAL INTERMODULATION DISTORTION (IMD) vs FREQUENCY 0 SFDR = 81.2 dBc SINAD = 70.4 dBFS SNR = 71.4 dBFS THD = 78 dBc −20 fIN1 = 190 MHz, –7 dBFS fIN2 = 185 MHz, –7 dBFS 2-Tone IMD = –84 dBFS SFDR = –89 dBFS −20 −40 Amplitude − dB −40 −60 −80 −100 −60 −80 −100 −120 −120 −140 −140 −160 −160 0 10 20 30 f − Frequency − MHz 40 0 10 20 30 f − Frequency − MHz G039 Figure 47. 40 G040 Figure 48. SFDR vs INPUT FREQUENCY SNR vs INPUT FREQUENCY 100 76 96 74 92 Gain = 0 dB 72 88 Gain = 3.5 dB SNR − dBFS SFDR − dBc 30 f − Frequency − MHz 0 Amplitude − dB SFDR = 83.5 dBc SINAD = 73.4 dBFS SNR = 74.3 dBFS THD = 82.6 dBc −20 84 80 Gain = 0 dB 76 72 70 Gain = 3.5 dB 68 66 68 64 64 60 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G041 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz Figure 49. Copyright © 2007–2008, Texas Instruments Incorporated G042 Figure 50. Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 31 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6143 (FS= 80 MSPS) (continued) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) SFDR vs INPUT FREQUENCY (LVDS interface) SNR vs INPUT FREQUENCY (LVDS interface) 100 76 96 74 92 Gain = 0 dB SFDR − dBc SNR − dBFS 72 88 Gain = 3.5 dB 84 80 76 Gain = 0 dB 70 Gain = 3.5 dB 68 72 66 68 64 64 60 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G043 Figure 51. SFDR vs INPUT FREQUENCY ACROSS GAINS SINAD vs INPUT FREQUENCY ACROSS GAINS 95 76 0 dB Input adjusted to get −1dBFS input 1 dB 3 dB 72 2 dB 6 dB 80 SINAD − dBFS 85 5 dB 0 dB 4 dB 75 1 dB 2 dB 3 dB 70 68 66 4 dB 70 5 dB 64 65 6 dB 62 60 60 0 100 200 300 400 fIN − Input Frequency − MHz 500 0 100 200 G045 Figure 53. PERFORMANCE vs AVDD 77 82 75 SNR 80 74 78 73 76 72 74 71 3.2 3.3 3.4 AVDD − Supply Voltage − V 3.5 100 77 fIN = 10.1 MHz AVDD = 3.3 V 76 SNR SFDR − dBc SFDR SNR − dBFS SFDR − dBc PERFORMANCE vs DRVDD 76 3.1 98 75 96 74 94 92 72 90 71 88 1.8 70 3.6 G047 73 SFDR 2.0 2.2 2.4 2.6 Submit Documentation Feedback 2.8 3.0 DRVDD − Supply Voltage − V Figure 55. 32 500 G046 102 78 84 72 3.0 400 Figure 54. 88 fIN = 70.1 MHz DRVDD = 3.3 V 300 fIN − Input Frequency − MHz 3.2 3.4 SNR − dBFS SFDR − dBc Input adjusted to get −1dBFS input 74 90 86 G044 Figure 52. 70 3.6 G048 Figure 56. Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6143 (FS= 80 MSPS) (continued) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) PERFORMANCE vs TEMPERATURE PERFORMANCE vs INPUT AMPLITUDE 95 77 110 SFDR 100 85 75 SNR 89 74 87 73 72 −20 80 80 75 SNR (dBFS) 70 60 70 65 SFDR (dBc) 50 60 40 fIN = 10.1 MHz 85 −40 90 0 20 40 60 T − Temperature − °C 55 30 −60 80 fIN = 20 MHz −50 −40 −30 −20 −10 50 0 Input Amplitude − dBFS G049 Figure 57. G050 Figure 58. PERFORMANCE vs CLOCK AMPLITUDE 92 PERFORMANCE vs INPUT CLOCK DUTY CYCLE 96 80 80 fIN = 10.1 MHz fIN = 20.1 MHz 90 SNR − dBFS 91 SNR − dBFS 76 SFDR − dBc, dBFS 93 SFDR − dBc 90 SFDR (dBFS) 94 79 79 86 77 84 76 82 75 SNR 80 78 1.0 1.5 2.0 2.5 92 78 90 77 88 76 86 75 74 84 73 82 72 3.0 80 Input Clock Amplitude − VPP SNR 73 72 30 35 40 45 50 55 60 65 70 Input Clock Duty Cycle − % G051 Figure 59. G052 Figure 60. OUTPUT NOISE HISTOGRAM WITH INPUTS TIED TO COMMON-MODE PERFORMANCE IN EXTERNAL REFERENCE MODE 40 92 82 fIN = 20.1 MHz External Reference Mode RMS (LSB) = 1.037 35 90 30 80 SFDR SFDR − dBc Occurence − % 74 25 20 15 88 78 86 76 SNR − dBFS 76 0.5 SFDR − dBc 78 SFDR SNR − dBFS SFDR − dBc 88 SNR − dBFS SFDR SNR 10 84 74 5 0 82 1.30 8204 8205 8206 8207 8208 8209 8210 8211 8212 8213 Output Code G053 1.35 1.40 1.45 1.55 1.60 1.65 72 1.70 VVCM − VCM Voltage − V Figure 61. Copyright © 2007–2008, Texas Instruments Incorporated 1.50 G054 Figure 62. Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 33 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6142 (FS= 65 MSPS) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) FFT for 20 MHz INPUT SIGNAL FFT for 90 MHz INPUT SIGNAL 0 0 SFDR = 91.3 dBc SINAD = 74.8 dBFS SNR = 75 dBFS THD = 89.5 dBc −20 −40 Amplitude − dB Amplitude − dB −40 −60 −80 −100 −60 −80 −100 −120 −120 −140 −140 −160 −160 0 10 20 30 f − Frequency − MHz 0 10 20 30 f − Frequency − MHz G055 G056 Figure 63. Figure 64. FFT for 230 MHz INPUT SIGNAL INTERMODULATION DISTORTION (IMD) vs FREQUENCY 0 0 SFDR = 83 dBc SINAD = 71.2 dBFS SNR = 71.9 dBFS THD = 79.8 dBc −20 fIN1 = 190 MHz, –7 dBFS fIN2 = 185 MHz, –7 dBFS 2-Tone IMD = –88 dBFS SFDR = –92 dBFS −20 −40 Amplitude − dB −40 Amplitude − dB SFDR = 83 dBc SINAD = 73.5 dBFS SNR = 74.4 dBFS THD = 82.2 dBc −20 −60 −80 −100 −60 −80 −100 −120 −120 −140 −140 −160 −160 0 10 20 f − Frequency − MHz 30 0 10 20 f − Frequency − MHz G057 Figure 65. 30 G058 Figure 66. SFDR vs INPUT FREQUENCY SNR vs INPUT FREQUENCY 100 76 96 74 88 84 80 76 Gain = 0 dB 72 Gain = 3.5 dB SNR − dBFS SFDR − dBc 92 Gain = 0 dB 72 70 Gain = 3.5 dB 68 66 68 64 64 60 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G059 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz Figure 67. 34 Submit Documentation Feedback G060 Figure 68. Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6142 (FS= 65 MSPS) (continued) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) SFDR vs INPUT FREQUENCY (LVDS interface) SNR vs INPUT FREQUENCY (LVDS interface) 100 76 96 74 Gain = 0 dB 88 72 Gain = 3.5 dB SNR − dBFS SFDR − dBc 92 84 80 76 Gain = 0 dB 70 Gain = 3.5 dB 68 72 66 68 64 64 60 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G061 Figure 69. SFDR vs INPUT FREQUENCY ACROSS GAINS SINAD vs INPUT FREQUENCY ACROSS GAINS 95 76 Input adjusted to get −1dBFS input Input adjusted to get −1dBFS input 74 90 3 dB 6 dB 80 0 dB 1 dB 72 SINAD − dBFS 1 dB 0 dB 5 dB 75 2 dB 70 68 3 dB 66 70 4 dB 64 4 dB 65 5 dB 60 0 100 200 300 400 fIN − Input Frequency − MHz 500 0 100 200 G063 PERFORMANCE vs AVDD fIN = 70.1 MHz DRVDD = 3.3 V 104 78 90 77 88 76 SNR 75 84 74 82 73 3.4 AVDD − Supply Voltage − V 3.5 SNR − dBFS SFDR SFDR − dBc 92 3.3 G065 76 SNR 102 75 100 74 98 73 SFDR 96 72 94 71 92 1.8 72 3.6 77 fIN = 10.1 MHz AVDD = 3.3 V 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 70 3.6 DRVDD − Supply Voltage − V Figure 73. Copyright © 2007–2008, Texas Instruments Incorporated G064 PERFORMANCE vs DRVDD 79 3.2 500 106 80 3.1 400 Figure 72. 96 86 300 fIN − Input Frequency − MHz Figure 71. SFDR − dBc 6 dB 62 60 80 3.0 2 dB SNR − dBFS SFDR − dBc 85 94 G062 Figure 70. G066 Figure 74. Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 35 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - ADS6142 (FS= 65 MSPS) (continued) All plots are at 25°C, AVDD = DRVDD = 3.3 V, maximum rated sampling frequency, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) PERFORMANCE vs TEMPERATURE PERFORMANCE vs INPUT AMPLITUDE 78 76 92 SNR − dBFS 75 SNR 74 88 73 0 20 40 60 80 T − Temperature − °C 80 75 SNR (dBFS) 70 70 60 65 SFDR (dBc) 50 60 55 30 −60 72 −20 80 40 fIN = 10.1 MHz 86 −40 90 fIN = 20.1 MHz −50 −40 −30 PERFORMANCE vs CLOCK AMPLITUDE fIN = 20.1 MHz 78 77 88 76 SNR 75 73 78 72 82 73 74 72 3.0 70 2.0 2.5 Input Clock Amplitude − VPP 71 fIN = 10.1 MHz 70 30 35 40 45 50 55 60 65 70 Input Clock Duty Cycle − % G069 Figure 77. G070 Figure 78. OUTPUT NOISE HISTOGRAM WITH INPUTS TIED TO COMMON-MODE PERFORMANCE IN EXTERNAL REFERENCE MODE 40 95 82 fIN = 20.1 MHz External Reference Mode RMS (LSB) = 1.041 35 93 30 80 SFDR SFDR − dBc Occurence − % 74 SNR 82 74 1.5 75 86 84 1.0 76 90 SFDR − dBc 90 77 SFDR 94 SNR − dBFS SFDR − dBc 98 79 SFDR 80 0.5 G068 PERFORMANCE vs INPUT CLOCK DUTY CYCLE 80 86 50 0 Figure 76. 96 92 −10 Input Amplitude − dBFS G067 Figure 75. 94 −20 SNR − dBFS 90 85 25 20 15 10 91 78 89 76 SNR 87 SNR − dBFS SFDR − dBc SFDR 94 90 SFDR (dBFS) 100 77 SFDR − dBc, dBFS 96 110 SNR − dBFS 98 74 5 0 85 1.30 8202 8203 8204 8205 8206 8207 8208 8209 8210 8211 Output Code G071 1.35 1.40 1.45 Submit Documentation Feedback 1.55 VVCM − VCM Voltage − V Figure 79. 36 1.50 1.60 1.65 72 1.70 G072 Figure 80. Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 TYPICAL CHARACTERISTICS - LOW SAMPLING FREQUENCIES All plots are at 25°C, AVDD = DRVDD = 3.3 V, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) FS = 40 MSPS SFDR vs INPUT FREQUENCY SNR vs INPUT FREQUENCY 100 76 96 74 Gain = 0 dB 72 88 SNR − dBFS SFDR − dBc 92 84 Gain = 3.5 dB 80 76 72 70 Gain = 3.5 dB 68 66 Gain = 0 dB 68 64 64 60 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G073 Figure 81. G074 Figure 82. FS = 25 MSPS SFDR vs INPUT FREQUENCY SNR vs INPUT FREQUENCY 76 100 74 90 SNR − dBFS SFDR − dBc 72 Gain = 3.5 dB 80 70 Gain = 0 dB 68 Gain = 3.5 dB 66 Gain = 0 dB 60 70 64 50 62 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz G075 0 50 100 150 200 250 300 350 400 450 500 fIN − Input Frequency − MHz Figure 83. Copyright © 2007–2008, Texas Instruments Incorporated G076 Figure 84. Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 37 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 COMMON PLOTS All plots are at 25°C, AVDD = DRVDD = 3.3 V, sine wave input clock, 1.5 VPP differential clock amplitude, 50% clock duty cycle, –1 dBFS differential analog input, internal reference mode, 0 dB gain, CMOS output interface (unless otherwise noted) POWER DISSIPATION vs SAMPLING FREQUENCY (DDR LVDS and CMOS) COMMON-MODE REJECTION RATIO vs FREQUENCY 0.8 0.7 PD − Power Dissipation − W 0 −10 −20 CMRR − dBc −30 −40 −50 −60 −70 −80 fIN = 2.5 MHz CL = 5 pF 0.6 0.5 LVDS 0.4 0.3 CMOS 0.2 0.1 −90 0.0 −100 0 50 100 150 200 250 0 300 f − Frequency − MHz 25 50 75 100 fS − Sampling Frequency − MSPS G077 Figure 85. 125 G078 Figure 86. DRVDD current vs SAMPLING FREQUENCY ACROSS LOAD CAPACITANCE (CMOS) 30 1.8 V, No Load DRVDD Current − mA 25 1.8 V, 5 pF 20 3.3 V, No Load 3.3 V, 5 pF 15 3.3 V, 10 pF 10 5 0 0 25 50 75 100 fS − Sampling Frequency − MSPS 125 G079 Figure 87. 38 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Contour Plots Across Input and Sampling Frequencies 125 120 90 fS - Sampling Frequency - MSPS 110 75 84 84 87 72 78 81 66 69 84 84 63 100 75 81 87 90 84 90 87 70 72 78 90 87 80 66 60 69 81 63 78 60 75 84 50 90 69 72 66 40 93 30 25 10 81 84 50 78 150 100 75 60 63 200 250 300 400 350 450 500 fIN - Input Frequency - MHz 60 65 75 70 80 85 90 95 SFDR - dBc M0049-15 Figure 88. SFDR Contour (no gain, Fs = 2 VPP) 125 120 84 87 87 87 84 75 78 81 fS - Sampling Frequency - MSPS 110 69 87 100 72 66 90 75 90 90 80 90 87 70 60 78 81 87 93 84 69 90 75 81 93 66 72 78 50 90 90 40 30 25 10 87 84 93 93 50 100 150 81 78 75 200 250 300 72 63 69 400 350 450 500 fIN - Input Frequency - MHz 60 65 70 75 80 85 90 SFDR - dBc 95 M0049-16 Figure 89. SFDR Contour (with 3.5 dB coarse gain, FS = 1.34 VPP) Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 39 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Contour Plots Across Input and Sampling Frequencies (continued) 125 120 66 74 fS - Sampling Frequency - MSPS 110 90 71 72 73 100 67 68 69 70 74 68 69 67 80 71 70 70 73 72 60 68 50 40 71 75 69 70 30 25 10 50 72 73 74 150 100 70 71 200 250 69 67 66 68 300 400 350 65 64 500 450 fIN - Input Frequency - MHz 64 68 66 70 72 74 SNR - dBFS M0048-15 Figure 90. SNR Contour (no gain, FS = 2 VPP) 125 120 68 69 70 72 67 66 fS - Sampling Frequency - MSPS 110 100 71 73 67 90 72 80 70 68 69 70 73 60 71 68 50 69 70 72 40 73 30 25 10 50 71 100 150 70 200 250 67 68 69 300 66 350 400 450 65 64 500 fIN - Input Frequency - MHz 64 66 68 70 72 SNR - dBFS 74 M0048-16 Figure 91. SNR Contour (with 3.5 dB coarse gain, FS = 1.34 VPP) 40 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 APPLICATION INFORMATION THEORY OF OPERATION The ADS614X devices are a family of low power, 14-bit pipeline ADCs in a CMOS process with up to a 125 MSPS sampling frequencies. These devices are based on switched capacitor technology and run off a single 3.3-V supply. The conversion process is initiated by the rising edge of the external input clock. Once the signal is captured by the input sample and hold, the input sample is sequentially converted by a series of lower 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 9 clock cycles. The output is available as 14-bit data, in DDR LVDS or CMOS and coded in either straight offset binary or binary 2s complement format. ANALOG INPUT The analog input consists of a switched-capacitor based differential sample and hold architecture, shown in Figure 92. This differential topology results in good ac-performance even for high input frequencies at high sampling rates. The INP and INM pins have to be externally biased around a common-mode voltage of 1.5 V available on the VCM pin. For a full-scale differential input, each input pin (INP, INM) has to swing symmetrically between VCM + 0.5 V and VCM – 0.5 V, resulting in a 2VPP differential input swing. The maximum swing is determined by the internal reference voltages REFP (2.5 V nominal) and REFM (0.5 V, nominal). Sampling Switch Lpkg »1 nH Sampling Capacitor RCR Filter INP Cbond »1 pF 25 W Resr 200 W Cpar2 1 pF 50 W 3.2 pF Csamp 4.0 pF Ron 10 W Cpar1 0.8 pF 50 W Lpkg »1 nH Ron 15 W Ron 15 W 25 W Csamp 4.0 pF INM Cbond »1 pF Resr 200 W Sampling Capacitor Cpar2 1 pF Sampling Switch Figure 92. Input Stage The input sampling circuit has a high 3dB bandwidth that extends up to 450 MHz (measured from the input pins to the voltage across the sampling capacitors). Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 41 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 1 0 Magnitude − dB −1 −2 −3 −4 −5 −6 −7 0 100 200 300 400 500 600 fIN − Input Frequency − MHz G080 Figure 93. ADC Analog Input Bandwidth Drive Circuit Requirements For optimum performance, the analog inputs must be driven differentially. This improves the common-mode noise immunity and even-order harmonic rejection. A 5-Ω resistor in series with each input pin is recommended to damp out ringing caused by the package parasitics. It is also necessary to present low impedance (< 50 Ω) for the common-mode switching currents. For example, this is achieved by using two resistors from each input terminated to the common-mode voltage (VCM). In addition to the above, the drive circuit may have to be designed to provide a low insertion loss over the desired frequency range and matched impedance to the source. While doing this, the ADC input impedance (Zin) must be considered. Over a wide frequency range, the input impedance can be approximated by a parallel combination of Rin and Cin (Zin = Rin||Cin). R − Resistance − kΩ 100 10 1 0.1 0.01 0 100 200 300 400 500 f − Frequency − MHz 600 G083 Figure 94. ADC Input Resistance, Rin 42 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 9 C − Capacitance − pF 8 7 6 5 4 3 2 1 0 0 100 200 300 400 500 f − Frequency − MHz 600 G084 Figure 95. ADC Input Capacitance, Cin Using RF-Transformer Based Drive Circuits Figure 96 shows a configuration using a single 1:1 turn ratio transformer (for example, Coilcraft WBC1-1) that can be used for low input frequencies (about 100 MHz). The single-ended signal is fed to the primary winding of the RF transformer. The transformer is terminated on the secondary side. Putting the termination on the secondary side helps to shield the kickbacks caused by the sampling circuit from the RF transformer’s leakage inductances. The termination is accomplished by two resistors connected in series, with the center point connected to the 1.5 V common mode (VCM pin). The value of the termination resistors (connected to common mode) has to be low (< 100 Ω) to provide a low-impedance path for the ADC common-mode switching current. TF_ADC 0.1 mF 5W INP 0.1 mF 25 W 25 W 5W INM 1 :1 VCM Figure 96. Single Transformer Drive Circuit At high input frequencies, the mismatch in the transformer parasitic capacitance (between the windings) results in degraded even-order harmonic performance. Connecting two identical RF transformers back-to-back helps minimize this mismatch, and good performance is obtained for high frequency input signals. Figure 97 shows an example using two transformers (Coilcraft WBC1-1). An additional termination resistor pair (enclosed within the dotted box in Figure 97) may be required between the two transformers to improve the balance between the P and M sides. The center point of this termination must be connected to ground. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 43 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 5W 0 .1mF INP 50 W 50 W 0 .1mF 50 W 50 W 5W INM 1:1 1:1 VCM Figure 97. Two Transformer Drive Circuit Using Differential Amplifier Drive Circuits Figure 98 shows a drive circuit using a differential amplifier (TI's THS4509) to convert a single-ended input to a differential output that can be interfaced to the ADC analog input pins. In addition to the single-ended to differential conversion, the amplifier also provides gain (10 dB in Figure 98). RFIL helps to isolate the amplifier outputs from the switching input of the ADC. Together with CFIL it also forms a low-pass filter that band-limits the noise (and signal) at the ADC input. As the amplifier output is ac-coupled, the common-mode voltage of the ADC input pins is set using two 200-Ω resistors connected to VCM. The amplifier output can also be dc-coupled. Using the output common-mode control of the THS4509, the ADC input pins can be biased to 1.5 V. In this case, use +4-V and –1-V supplies for the THS4509 so that its output common-mode voltage (1.5 V) is at mid-supply. RF +VS 500 W 0.1 mF RS 0.1 mF 10 mF RFIL 0.1 mF 5W INP RG 0.1 mF RT CFIL 200 W CFIL 200 W CM THS4509 RG RFIL INM 5W 0.1 mF 500 W RS || RT VCM 0.1 mF –VS ADS614x 0.1 mF 10 mF 0.1 mF RF Figure 98. Drive Circuit Using the THS4509 See the EVM User Guide (SLWU028) for more information. 44 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Input Common Mode To ensure a low-noise common-mode reference, the VCM pin is filtered with a 0.1-µF low-inductance capacitor connected to ground. The VCM pin is designed to directly drive the ADC inputs. The input stage of the ADC sinks a common-mode current in the order of 180 µA (at 125 MSPS). Equation 1 describes the dependency of the common-mode current and the sampling frequency. Fs 180 mA x 125 MSPS (1) Equation 1 helps to design the output capability and impedance of the CM driving circuit. REFERENCE The ADS614X have built-in internal references REFP and REFM, requiring no external components. Design schemes are used to linearize the converter load seen by the references; this and the integration of the requisite reference capacitors on-chip eliminates the need for external decoupling. The full-scale input range of the converter is controlled in the external reference mode as explained below. The internal or external reference modes can be selected by programming the serial interface register bit (Table 5). INTREF INTERNAL REFERENCE VCM 1 kW 4 kW INTREF EXTREF REFM REFP Figure 99. Reference Section Internal Reference When the device is in internal reference mode, the REFP and REFM voltages are generated internally. Common-mode voltage (1.5 V nominal) is output on the VCM pin, which can be used to externally bias the analog input pins. External Reference When the device is in external reference mode, VCM acts as a reference input pin. The voltage forced on the VCM pin is buffered and gained by 1.33 internally, generating the REFP and REFM voltages. The differential input voltage corresponding to full-scale is given by Equation 2. Full−scale differential input pp + (Voltage forced on VCM) 1.33 (2) In this mode, the 1.5-V common-mode voltage to bias the input pins has to be generated externally. There is no change in performance compared to internal reference mode. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 45 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 COARSE GAIN AND PROGRAMMABLE FINE GAIN The ADS614X include gain settings that can be used to improve SFDR performance (compared to 0 dB gain mode). The gain settings are 3.5 dB coarse gain and 0 dB to 6 dB programmable fine gain. For each gain setting, the analog input full-scale range scales proportionally, as shown in Table 13. The coarse gain is a fixed setting of 3.5 dB and is designed to improve SFDR with little degradation in SNR (as shown in Figure 13 and Figure 14). The fine gain is programmable in 1 dB steps from 0 dB to 6 dB. With fine gain, SFDR improvement is also achieved, but at the expense of SNR (there is about 1 dB SNR degradation for every 1 dB of fine gain). So, the fine gain can be used to trade-off between SFDR and SNR. The coarse gain makes it possible to get the best SFDR but without losing SNR significantly. At high input frequencies, the gains are especially useful as the SFDR improvement is significant with marginal degradation in SINAD. The gains can be programmed using the register bits (see Table 5) and (see Table 10). Note that the default gain after reset is 0 dB. Table 13. Full-Scale Range Across Gains GAIN, dB TYPE FULL-SCALE RANGE, VPP 0 Default after reset 2.00 3.5 Coarse setting (fixed) 1.34 1 1.78 2 1.59 3 Fine gain (programmable) 4 46 1.42 1.26 5 1.12 6 1.00 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 CLOCK INPUT The clock inputs of the ADS614X can be driven differentially (SINE, LVPECL, or LVDS) or single-ended (LVCMOS), with little or no difference in performance between configurations. The common-mode voltage of the clock inputs is set to VCM using internal 5-kΩ resistors as shown in Figure 100. This allows the use of transformer-coupled drive circuits for the sine wave clock, or ac-coupling for the LVPECL, LVDS clock sources (see Figure 102 and Figure 103). For best performance, it is recommended to drive the clock inputs differentially, reducing susceptibility to common-mode noise. In this case, it is best to connect both clock inputs to the differential input clock signal with 0.1-µF capacitors, as shown in Figure 102. A single-ended CMOS clock can be ac-coupled to the CLKP input, with CLKM connected to ground with a 0.1-µF capacitor, as shown in Figure 103. For high input frequency sampling, a clock source with very low jitter is recommended. Band-pass filtering of the clock source can help reduce the effect of jitter. There is no change in performance with a non-50% duty cycle clock input. Figure 24 shows the performance of the ADC versus clock duty cycle. Clock Buffer Lpkg » 1 nH 10 W CLKP Cbond » 1 pF Ceq Ceq 5 kW Resr » 100 W VCM 6 pF 5 kW Lpkg » 1 nH 10 W CLKM Cbond » 1 pF Resr » 100 W Ceq » 1 to 3 pF, equivalent input capacitance of clock buffer Figure 100. Internal Clock Buffer Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 47 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 1000 Impedance (Magnitude) − Ω 900 800 700 600 500 400 300 200 100 0 0 25 50 75 100 125 Clock Frequency − MHz G082 Figure 101. Clock Buffer Input Impedance 0.1 mF CLKP Differential Sine-Wave or PECL or LVDS Clock Input 0.1 mF CLKM ADS614x Figure 102. Differential Clock Driving Circuit 0.1 mF CMOS Clock Input CLKP 0.1 mF CLKM ADS614x Figure 103. Single-Ended Clock Driving Circuit 48 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 POWER-DOWN MODES The ADS614X have four power-down modes – global power down, standby, output buffer disable, and input clock stopped. These modes can be set using the serial interface or using the parallel interface (pins SDATA and PDN). Table 14. Power-Down Modes POWER-DOWN MODES PARALLEL INTERFACE SERIAL INTERFACE REGISTER BIT (Table 5) TOTAL POWER, mW WAKE-UP TIME (to valid data) SDATA PDN Normal operation Low Low =0 and =0 417 Standby Low High =0 and =1 72 Slow (15 µs) Output buffer disable High Low =1 and =0 408 Fast (200 ns) Global power down High High =1 and =1 30 Slow (15 µs) - Global Power Down In this mode, the A/D converter, internal references, and the output buffers are powered down and the total power dissipation reduces to about 30 mW. The output buffers are in a high-impedance state. The wake-up time from the global power down to output data becoming valid in normal mode is a maximum of 50 µs. Note that after coming out of global power down, optimum performance is achieved after the internal reference voltages have stabilized (about 1 ms). Standby Only the A/D converter is powered down and total power dissipation is approximately 72 mW. The wake-up time from standby to output data becoming valid is a maximum of 50 µs. Output Buffer Disable The data output buffers can be disabled, reducing total power to about 408 mW. With the buffers disabled, the outputs are in a high-impedance state. The wake-up time from this mode to data becoming valid in normal mode is a maximum of 500 ns in LVDS mode and 200 ns in CMOS mode. Input Clock Stop The converter enters this mode when the input clock frequency falls below 1 MSPS. Power dissipation is approximately 120 mW, and the wake-up time from this mode to data becoming valid in normal mode is a maximum of 50 µs. Power Supply Sequence During power-up, the AVDD and DRVDD supplies can come up in any sequence. The two supplies are separated inside the device. Externally, they can be driven from separate supplies or from a single supply. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 49 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 DIGITAL OUTPUT INTERFACE The ADS614X output 14 data bits together with an output clock. The output interface is either parallel CMOS or DDR LVDS voltage levels and can be selected using the serial register bit or parallel pin SEN. Parallel CMOS Interface In CMOS mode, the output buffer supply (DRVDD) can be operated over a wide range from 1.8 V to 3.3 V (typical). Each data bit is output on a separate pin as a CMOS voltage level, every clock cycle. For DRVDD ≥ 2.2 V, it is recommended to use the CMOS output clock (CLKOUT) to latch data in the receiving chip. The rising edge of CLKOUT can be used to latch data in the receiver, even at the highest sampling speed (125 MSPS). It is recommended to minimize the load capacitance seen by the data and clock output pins by using short traces to the receiver. Also, match the output data and clock traces to minimize the skew between them. For DRVDD < 2.2 V, it is recommended to use an external clock (for example, input clock delayed to get desired setup/hold times). Output Clock Position Programmability There is an option to shift (delay) the output clock position so that the setup time increases by 400 ps (typical, with respect to the default timings specified). This may be useful if the receiver needs more setup time, especially at high sampling frequencies. This can be programmed using the serial interface register bit (Table 6). Output Buffer Strength Programmability Switching noise (caused by CMOS output data transitions) can couple into the analog inputs during the instant of sampling and degrade the SNR. The coupling and SNR degradation increases as the output buffer drive is made stronger. To minimize this, the ADS614X CMOS output buffers are designed with a controlled drive strength for the best SNR. The default drive strength also ensures a wide data stable window for load capacitances up to 5 pF and a DRVDD supply voltage ≥ 2.2 V. To ensure a wide data stable window for load capacitances > 5 pF, there is an option to increase the drive strength using the serial interface (, see Table 12). Note that for a DRVDD supply voltage < 2.2 V, it is recommended to use the maximum drive strength (for any value of load capacitance). CMOS Mode Power Dissipation With CMOS outputs, the DRVDD current scales with the sampling frequency and the load capacitance on every output pin. The maximum DRVDD current occurs when each output bit toggles between 0 and 1 every clock cycle. In actual applications, this condition is unlikely to occur. The actual DRVDD current would be determined by the average number of output bits switching, which is a function of the sampling frequency and the nature of the analog input signal. Digital current due to CMOS output switching = CL × DRVDD x (N x FAVG) where CL = load capacitance, N × FAVG = average number of output bits switching Figure 87 shows the current with various load capacitances across sampling frequencies with a 2-MHz analog input frequency. 50 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Pins OVR CLKOUT D0 D1 CMOS Output Buffers D2 D3 D4 D5 D6 14 bit ADC data D7 D8 D9 D10 D11 D12 D13 ADS614X Figure 104. CMOS Output Buffers Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 51 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 DDR LVDS Interface The LVDS interface works only with a 3.3-V DRVDD supply. In this mode, the 14 data bits and the output clock are available as LVDS (Low Voltage Differential Signal) levels. Two successive data bits are multiplexed and output on each LVDS differential pair every clock cycle (DDR - Double Data Rate, see Figure 105 ). So, there are 7 LVDS output pairs for the 14 data bits and 1 LVDS output pair for the output clock. LVDS Buffer Current Programmability The default LVDS buffer output current is 3.5 mA. When terminated by 100 Ω, this results in a 350-mV single-ended voltage swing (700-mVPP differential swing). The LVDS buffer currents can also be programmed to 2.5 mA, 4.5 mA, and 1.75 mA (register bits , see Table 11). In addition, there is a current double mode, where this current is doubled for the data and output clock buffers (register bits , see Table 11). Pins CLKOUTP Output Clock CLKOUTM D0_D1_P Data bits D0, D1 D0_D1_M LVDS Buffers D2_D3_P Data bits D2, D3 D2_D3_M D4_D5_P Data bits D4, D5 D4_D5_M 14-Bit ADC Data D6_D7_P Data bits D6, D7 D6_D7_M D8_D9_P Data bits D8, D9 D8_D9_M D10_D11_P Data bits D10, D11 D10_D11_M D12_D13_P Data bits D12, D13 D12_D13_M ADS614x Figure 105. DDR LVDS Outputs 52 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Even data bits D0, D2, D4, D6, D8, D10, and D12 are output at the rising edge of CLKOUTP and the odd data bits D1, D3, D5, D7, D9, D11, and D13 are output at the falling edge of CLKOUTP. Both the rising and falling edges of CLKOUTP must be used to capture all 14 data bits (see Figure 106). CLKOUTM CLKOUTP D0_D1_P, D0_D1_M D0 D1 D0 D1 D2_D3_P, D2_D3_M D2 D3 D2 D3 D4_D5_P, D4_D5_M D4 D5 D4 D5 D6_D7_P, D6_D7_M D6 D7 D6 D7 D8_D9_P, D8_D9_M D8 D9 D8 D9 D10_D11_P, D10_D11_M D10 D11 D10 D11 D12_D13_P, D12_D13_M D12 D13 D12 D13 Sample N Sample N+1 Figure 106. DDR LVDS Interface LVDS Buffer Internal Termination An internal termination option is available (using the serial interface), by which the LVDS buffers are differentially terminated inside the device. The termination resistances available are – 300 Ω, 185 Ω, and 150 Ω (nominal with ±20% variation). Any combination of these three terminations can be programmed; the effective termination is the parallel combination of the selected resistances. This results in eight effective terminations from open (no termination) to 65 Ω. The internal termination helps to absorb any reflections coming from the receiver end, improving the signal integrity. With 100-Ω internal and 100-Ω external termination, the voltage swing at the receiver end is halved (compared to no internal termination). The voltage swing can be restored by using the LVDS current double mode. Figure 107 and Figure 108 compare the LVDS eye diagrams without and with internal termination (100 Ω). With internal termination, the eye looks clean even with 10-pF load capacitance (from each output pin to ground). The termination is programmed using register bits and (see Table 11). Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 53 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 Figure 107. LVDS Eye Diagram - No Internal Termination 5-pF Load Capacitance Blue Trace - Output Clock (CLKOUT) Pink Trace - Output Data Figure 108. LVDS Eye Diagram with 100-Ω Internal Termination 10-pF Load Capacitance Blue Trace - Output Clock (CLKOUT) Pink Trace - Output Data Output Data Format Two output data formats are supported – 2s complement and offset binary. They can be selected using the parallel control pin SEN or the serial interface register bit (see Table 8). Output Timings The tables below show the timings at lower sampling frequencies. Table 15. Timing Characteristics at Lower Sampling Frequencies Fs, MSPS tsu DATA SETUP TIME, ns MIN TYP MAX th DATA HOLD TIME, ns MIN TYP (1) (2) tPDI CLOCK PROPAGATION DELAY, ns MAX MIN TYP MAX 5 6.5 7.9 CMOS INTERFACE, DRVDD = 2.5 V to 3.3 V 40 11.3 12.8 10 11.2 20 23 25 21 23 10 48 50 46 48 DDR LVDS INTERFACE, DRVDD = 3.3 V (1) (2) 54 40 10.2 10.8 0.7 1.7 4.3 5.8 7.3 20 22 23 0.7 1.7 4.5 6.5 8.5 10 47 48 0.7 1.7 4.5 6.5 8.5 Timing parameters are specified by design and characterization and not tested in production. Timings are specified with default output buffer drive strength and CL= 5 pF. Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 BOARD DESIGN CONSIDERATIONS Grounding 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 EVM User Guide (SLWU028) for details on layout and grounding. Supply Decoupling As the ADS614X already include internal decoupling, minimal external decoupling can be used without loss in performance. Note that decoupling capacitors can help filter external power supply noise, so the optimum number of capacitors would depend on the actual application. The decoupling capacitors should be placed very close to the converter supply pins. It is recommended to use separate supplies for the analog and digital supply pins to isolate digital switching noise from sensitive analog circuitry. In case only a single 3.3-V supply is available, it should be routed first to AVDD. It can then be tapped and isolated with a ferrite bead (or inductor) with decoupling capacitor, before being routed to DRVDD. Exposed Thermal Pad It is necessary to solder the exposed pad at the bottom of the package to a ground plane for best thermal performance. For detailed information, see application notes QFN Layout Guidelines (SLOA122) and QFN/SON PCB Attachment (SLUA271). Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 55 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 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. Aperture Uncertainty (Jitter) The sample-to-sample variation in aperture delay. Clock Pulse Width/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 certified 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 Nonlinearity (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’s 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 The gain error is the deviation of the ADC’s actual input full-scale range from its ideal value. The gain error is given as a percentage of the ideal input full-scale range. Offset Error The offset error is the difference, given in number of LSBs, between the ADC’s actual average idle channel output code and the ideal average idle channel output code. This quantity is often mapped into mV. 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. It is calculated by dividing the maximum deviation of the parameter across the TMIN to TMAX range by the difference TMAX–TMIN. 56 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 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. P SNR + 10Log 10 s PN (4) 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’s 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. Ps SINAD + 10Log 10 PN ) PD (5) 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’s full-scale range. Effective Number of Bits (ENOB) The ENOB is a measure of a converter’s performance as compared to the theoretical limit based on quantization noise. ENOB + SINAD * 1.76 6.02 (6) Total Harmonic Distortion (THD) THD is the ratio of the power of the fundamental (PS) to the power of the first nine harmonics (PD). P THD + 10Log 10 s PN (7) 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’s full-scale range. DC Power Supply Rejection Ratio (DC PSRR) The 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. Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 57 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 AC Power Supply Rejection Ratio (AC PSRR) AC PSRR is the measure of rejection of variations in the supply voltage of the ADC. If ΔVSUP is the change in the supply voltage and ΔVOUT is the resultant change in the ADC output code (referred to the input), then DVOUT (Expressed in dBc) PSRR = 20Log 10 DVSUP (8) Common-Mode Rejection Ratio (CMRR) CMRR is the measure of rejection of variations in the input common-mode voltage of the ADC. If ΔVcm is the change in the input common-mode voltage and ΔVOUT is the resultant change in the ADC output code (referred to the input), then DVOUT (Expressed in dBc) CMRR = 20Log10 DVCM (9) Voltage Overload Recovery The number of clock cycles taken to recover to less than 1% error for a 6-dB overload on the analog inputs. A 6-dBFS sine wave at Nyquist frequency is used as the test stimulus. 58 Submit Documentation Feedback Copyright © 2007–2008, Texas Instruments Incorporated Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 ADS6145, ADS6144 ADS6143, ADS6142 www.ti.com SLWS198B – JULY 2007 – REVISED MARCH 2008 REVISION HISTORY Changes from Revision A (October 2007) to Revision B ............................................................................................... Page • • • • • Added maximum DRVDD current footnote ........................................................................................................................... 5 Added SCLK and SEN pin function footnote ......................................................................................................................... 8 Changed DDR LVDS output data sequence in Figure 1 ..................................................................................................... 11 Changed pin configuration (CMOS mode) information........................................................................................................ 21 Changed pin configuration (LVDS mode) information ......................................................................................................... 23 Copyright © 2007–2008, Texas Instruments Incorporated Submit Documentation Feedback Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142 59 PACKAGE OPTION ADDENDUM www.ti.com 23-Apr-2022 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) ADS6142IRHBT ACTIVE VQFN RHB 32 250 RoHS & Green NIPDAUAG Level-3-260C-168 HR -40 to 85 AZ6142 ADS6143IRHBT ACTIVE VQFN RHB 32 250 RoHS & Green NIPDAU Level-3-260C-168 HR -40 to 85 AZ6143 ADS6144IRHBT ACTIVE VQFN RHB 32 250 RoHS & Green NIPDAU Level-3-260C-168 HR -40 to 85 AZ6144 ADS6145IRHBT ACTIVE VQFN RHB 32 250 RoHS & Green NIPDAU Level-3-260C-168 HR -40 to 85 AZ6145 (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