AD5750

Industrial Current/Voltage Output Driver with Programmable Ranges AD5750/AD5750-1 FEATURES Current output ranges: 4 mA to 20 mA, 0 mA to 20 mA or 0 mA to 24 mA, ±20 mA, and ±24 mA ±0.03% FSR total unadjusted error (TUE) ±5 ppm/°C typical output drift Voltage output ranges: 0 V to 5 V, 0 V to 10 V, ±5 V, and ±10 V, with 20% overrange ±0.02% FSR TUE ±3 ppm/°C typical output drift Flexible serial digital interface On-chip output fault detection PEC error checking Asynchronous CLEAR function Flexible power-up condition to 0 V or tristate Power supply range AVDD: +12 V (± 10%) to +24 V (± 10%) AVSS: −12 V (± 10%) to −24 V (± 10%) Output loop compliance to AVDD − 2.75 V Temperature range: −40°C to +105°C 32-lead, 5 mm × 5 mm LFCSP package The output current range is programmable across five current ranges: 4 mA to 20 mA, 0 mA to 20 mA or 0 mA to 24 mA, ±20 mA, and ±24 mA. An overrange of 2% is available on the unipolar current ranges. Voltage output is provided from a separate pin that can be configured to provide 0 V to 5 V, 0 V to 10 V, ±5 V, or ±10 V output ranges. An overrange of 20% is available on the voltage ranges. Analog outputs are short-circuit and open-circuit protected and can drive capacitive loads of 1 μF and inductive loads of 0.1 H. The device is specified to operate with a power supply range from ±12 V to ±24 V. Output loop compliance is 0 V to AVDD − 2.75 V. The flexible serial interface is SPI and MICROWIRE compatible and can be operated in 3-wire mode to minimize the digital isolation required in isolated applications. The interface also features an optional PEC error checking feature using CRC-8 error checking, useful in industrial environments where data communication corruption can occur. The device also includes a power-on reset function, ensuring that the device powers up in a known state (0 V or tristate), and an asynchronous CLEAR pin that sets the outputs to zero scale/midscale voltage output or the low end of the selected current range. An HW SELECT pin is used to configure the part for hardware or software mode on power-up. Table 1. Related Device Part Number AD5422 Description Single-channel, 16-bit, serial input current source and voltage output DAC APPLICATIONS Process control Actuator control PLCs GENERAL DESCRIPTION The AD5750/AD5750-1 are single-channel, low cost, precision voltage/current output drivers with hardware- or softwareprogrammable output ranges. The software ranges are configured via an SPI-/MICROWIRE™-compatible serial interface. The AD5750/AD5750-1 target applications in PLC and industrial process control. The analog input to the AD5750/AD5750-1 is provided from a low voltage, single-supply digital-to-analog converter (DAC) and is internally conditioned to provide the desired output current/voltage range. Analog input ranges available are 0 V to 2.5 V (AD5750-1) or 0 V to 4.096 V (AD5750). Rev. A Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2009 Analog Devices, Inc. All rights reserved. AD5750/AD5750-1 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Functional Block Diagram .............................................................. 3 Specifications..................................................................................... 4 Timing Characteristics ................................................................ 8 Absolute Maximum Ratings.......................................................... 10 ESD Caution ................................................................................ 10 Pin Configuration and Function Descriptions ........................... 11 Typical Performance Characteristics ........................................... 13 Voltage Output ............................................................................ 13 Current Output ........................................................................... 17 Terminology .................................................................................... 22 Theory of Operation ...................................................................... 23 Software Mode ............................................................................ 23 Current Output Architecture .................................................... 25 Driving Inductive Loads ............................................................ 25 Power-On State of AD5750/AD5750-1 ................................... 25 Default Registers at Power-On ................................................. 26 Reset Function ............................................................................ 26 OUTEN........................................................................................ 26 Software Control ........................................................................ 26 Hardware Control ...................................................................... 28 Transfer Function ....................................................................... 28 Detailed Description of Features .................................................. 29 Output Fault Alert—Software Mode ....................................... 29 Output Fault Alert—Hardware Mode ..................................... 29 Voltage Output Short-Circuit Protection ................................ 29 Asynchronous Clear (CLEAR) ................................................. 29 External Current Setting Resistor ............................................ 30 Programmable Overrange Modes ............................................ 30 Packet Error Checking ............................................................... 30 Applications Information .............................................................. 31 Transient Voltage Protection .................................................... 31 Thermal Considerations............................................................ 31 Layout Guidelines....................................................................... 31 Galvanically Isolated Interface ................................................. 32 Microprocessor Interfacing ....................................................... 32 Outline Dimensions ....................................................................... 33 Ordering Guide .......................................................................... 33 REVISION HISTORY 8/09—Rev. 0 to Rev. A Added AD5750-1 ................................................................ Universal Changes to Features and General Description Sections.............. 1 Changes to Table 2 ............................................................................ 4 Changes to Theory of Operation Section and Figure 51........... 23 Change to Figure 52 and Table 6 Title ......................................... 24 Changes to Current Output Architecture Section and Power-On State of AD5750/AD5750-1 .......................................................... 25 Changes to Transfer Function Section......................................... 28 Changes to Programmable Overrange Modes Section.............. 30 Changes to Ordering Guide .......................................................... 33 7/09—Revision 0: Initial Version Rev. A | Page 2 of 36 AD5750/AD5750-1 FUNCTIONAL BLOCK DIAGRAM DVCC GND CLEAR CLRSEL SCLK/OUTEN* SDIN/R0* SYNC/ RSET* SDO/VFAULT* HW SELECT INPUT SHIFT REGISTER AND CONTROL LOGIC STATUS REGISTER R2 VDD R3 VOUT RANGE SCALING VOUT SHORT FAULT VSENSE– AVDD GND COMP1 COMP2 AD5750/AD5750-1 VSENSE+ VOUT VIN VREF RESET IOUT RANGE SCALING RSET Vx** REXT1 REXT2 IOUT OVERTEMP FAULT/TEMP* NC/IFAULT* VOUT SHORT FAULT IOUT OPEN FAULT POWERON RESET VSS IOUT OPEN FAULT AD2/ R1* AD1/ R2* AD0/ R3* AVSS Figure 1. Rev. A | Page 3 of 36 07268-001 * DENOTES SHARED PIN. SOFTWARE MODE DENOTED BY REGULAR TEXT, HARDWARE MODE DENOTED BY ITALIC TEXT. FOR EXAMPLE, FOR FAULT/TEMP PIN, IN SOFTWARE MODE, THIS PIN TAKES ON FAULT FUNCTION. IN HARDWARE MODE, THIS PIN TAKES ON TEMP FUNCTION. ** Vx IS AN INTERNAL BIAS VOLTAGE (CAN BE GROUND OR OTHER VOLTAGE) THAT IS USED TO GENERATE THE INTERNAL SENSE CURRENTS NEEDED FOR THE CURRENT OUTPUTS. AD5750/AD5750-1 SPECIFICATIONS AVDD/AVSS = ±12 V (± 10%) to ±24 V (± 10%), DVCC = 2.7 V to 5.5 V, GND = 0 V. IOUT: RLOAD = 300 Ω. All specifications TMIN to TMAX, unless otherwise noted. Table 2. Parameter 1 INPUT VOLTAGE RANGE Min Typ 0 to 4.096 0 to 2.5 Input Leakage Current REFERENCE INPUT Reference Input Voltage −1 4.096 +1 Max Unit V Test Conditions/Comments Output unloaded AD5750 AD5750-1 μA V AD5750; external reference needs to be exactly as stated; otherwise, accuracy errors show up as error in output AD5750-1; external reference needs to be exactly as stated; otherwise, accuracy errors show up as error in output 1.25 V Input Leakage Current VOLTAGE OUTPUT Output Voltage Ranges −1 0 0 −5 −10 +1 5 10 +5 +10 6 μA V V V V V AVDD needs to have minimum 1.3 V headroom or >11.3 V AVDD/AVSS needs to have minimum 1.3 V headroom or >±11.3 V Programmable overranges; see the Detailed Description of Features section Output Voltage Overranges 0 0 −6 −12 −2.5 Accuracy Total Unadjusted Error (TUE) B Version 2 A Version2 Relative Accuracy (INL) Bipolar Zero Error (Offset at Midscale) 12 +6 +12 +2.5 V V V V −0.1 −0.05 −0.3 −0.1 −0.02 −10 −8 −5 −4 −10 −8 −5 −4 −5 −4 −3 ±0.02 ±0.05 ±0.005 ±0.5 ±0.3 ±1.5 ±0.5 ±0.3 ±1 ±0.5 +0.1 +0.05 +0.3 +0.1 +0.02 +10 +8 +5 +4 +10 +8 +5 +4 +5 +4 +3 Bipolar Zero Error TC Zero-Scale Error 3 Zero-Scale Error TC3 Zero-Scale/Offset Error % FSR % FSR % FSR % FSR % FSR mV mV mV mV ppm FSR/°C mV mV mV mV ppm FSR/°C mV mV mV TA = 25°C TA = 25°C ±10 V range TA = 25°C, ±10 V range ±5 V range TA = 25°C, ± 5 V range All bipolar ranges ±10 V range TA = 25°C, ±10 V range ± 5 V range TA = 25°C, ±5 V range All bipolar ranges 0 V to 10 V range TA = 25°C, 0 V to 10 V range 0 V to 5 V range Rev. A | Page 4 of 36 AD5750/AD5750-1 Parameter 1 Offset Error TC3 Gain Error Gain Error TC3 Full-Scale Error Full-Scale Error TC3 VOLTAGE OUTPUT CHARACTERISTICS3 Headroom Short-Circuit Current Load Capacitive Load Stability RLOAD = ∞ RLOAD = 2 kΩ RLOAD = ∞ Min −2.2 −0.05 −0.04 −0.05 −0.04 Typ ±0.3 ±2 ±0.015 ±0.5 ±0.015 ±1.5 Max +2.2 +0.05 +0.04 +0.05 +0.04 Unit mV ppm FSR/°C % FSR % FSR ppm FSR/°C % FSR % FSR ppm FSR/°C V mA kΩ nF nF μF Test Conditions/Comments TA = 25°C, 0 V to 5 V range All unipolar ranges All bipolar/unipolar ranges TA = 25°C All bipolar/unipolar ranges TA = 25°C 1.3 15 1 1 1 2 Output unloaded TA = 25°C External compensation capacitor required; see the Driving Inductive Loads section Specified with 2 kΩ || 220 pF, ±0.05% Specified with 2 kΩ || 220 pF, ±0.05% Specified with 2 kΩ || 220 pF 0.1 Hz to 10 Hz bandwidth 100 kHz bandwidth Measured at 10 kHz; specified with 2 kΩ || 220 pF 200 mV, 50 Hz/60 Hz sine wave superimposed on power supply voltage Outputs unloaded DC Output Impedance 0 V to 5 V range, ¼ to ¾ Step 0 V to 5 V range, 40 mV Input Step Slew Rate Output Noise Output Noise Spectral Density AC PSRR 0.12 7 4.5 2 2.5 45.5 165 −65 Ω μs μs V/μs μV rms μV rms nV/√Hz dB DC PSRR CURRENT OUTPUT Output Current Ranges 10 0 0 4 −20 −24 0 0 4 24 20 20 +20 +24 24.5 20.4 20.4 μV/V mA mA mA mA mA mA mA mA Output Current Overranges See the Detailed Description of Features section See the Detailed Description of Features section See the Detailed Description of Features section ACCURACY, INTERNAL RSET Total Unadjusted Error (TUE) B Version2 A Version2 Relative Accuracy (INL) Offset Error −0.2 −0.08 −0.5 −0.3 −0.02 −0.03 −16 −10 −50 −26 ±0.03 ±0.15 ±0.01 ±0.015 +0.2 +0.08 +0.5 +0.3 +0.02 +0.03 +16 +10 +50 +26 % FSR % FSR % FSR % FSR % FSR % FSR μA μA μA μA TA = 25°C TA = 25°C Unipolar ranges Bipolar ranges 4 mA to 20 mA, 0 mA to 20 mA, 0 mA to 24 mA ranges TA = 25°C ±20 mA, ±24 mA ranges TA = 25°C +5 +8 Rev. A | Page 5 of 36 AD5750/AD5750-1 Parameter 1 Offset Error TC3 Bipolar Zero Error Bipolar Zero TC3 Gain Error Min −35 −24 −0.2 −0.25 −0.03 Gain TC3 Full-Scale Error Full-Scale TC3 ACCURACY, EXTERNAL RSET Total Unadjusted Error (TUE) B Version2 A Version2 Relative Accuracy (INL) −0.2 −0.125 Typ ±3 +15 ±0.5 Max +35 +24 +0.2 +0.25 +0.03 +0.2 +0.125 Unit ppm FSR/°C μA μA ppm FSR/°C % FSR % FSR % FSR ppm FSR/°C % FSR % FSR ppm FSR/°C Test Conditions/Comments All ranges ±20 mA, ±24 mA ranges TA = 25°C 4 mA to 20 mA, 0 mA to 20 mA, 0 mA to 24 mA ranges ±20 mA, ±24 mA ranges TA = 25°C All ranges All ranges TA = 25°C All ranges ±0.006 ±8 ±0.02 ±4 −0.1 −0.08 −0.3 −0.1 −0.02 −0.03 −14 −11 −20 −15 ±0.03 ±0.02 ±0.01 ±0.015 +0.1 +0.08 +0.3 +0.1 +0.02 +0.03 +14 +11 +20 +15 +32 +22 +0.08 +0.07 +0.1 +0.07 % FSR % FSR % FSR % FSR % FSR % FSR μA μA μA μA ppm FSR/°C μA μA ppm FSR/°C % FSR % FSR ppm FSR/°C % FSR % FSR ppm FSR/°C V TA = 25° TA = 25°C 4 mA to 20 mA, 0 mA to 20 mA, 0 mA to 24 mA ranges ±20 mA, ±24 mA ranges 4 mA to 20 mA, 0 mA to 20 mA, 0 mA to 24 mA ranges TA = 25°C ±20 mA, ±24 mA ranges TA = 25°C All ranges All ranges TA = 25°C All ranges TA = 25°C All ranges All ranges TA = 25°C All ranges Offset Error +5 +8 ±2 +12 ±0.5 ±0.02 ±1 ±0.02 ±2 Offset Error TC3 Bipolar Zero Error Bipolar Zero TC3 Gain Error Gain TC Full-Scale Error Full-Scale TC3 CURRENT OUTPUT CHARACTERISTICS3 Current Loop Compliance Voltage Resistive Load Inductive Load −32 −22 −0.08 −0.07 −0.1 −0.07 0 AVDD − 2.75 See test conditions/comments column See test conditions/comments column Chosen such that compliance is not exceeded Needs appropriate capacitor at higher inductance values; see the Driving Inductive Loads section μs μs μA/V MΩ Gain 250 Ω load 250 Ω load Settling Time 4 mA to 20 mA, Full-Scale Step 4 mA to 20 mA Range, 120 μA Step DC PSRR Output Impedance VOUT/VSENSE− Error 8.5 1.2 1 130 0.9994 1.0006 Error in VOUT voltage due to changes in VSENSE−; specified as gain, for example, if VSENSE− moves by 1 V, then VOUT moves by 0.9994 V Rev. A | Page 6 of 36 AD5750/AD5750-1 Parameter 1 DIGITAL INPUT Input High Voltage, VIH Input Low Voltage, VIL Input Current Pin Capacitance DIGITAL OUTPUTS3 FAULT, IFAULT, TEMP, VFAULT Output Low Voltage, VOL Output High Voltage, VOH SDO Output Low Voltage, VOL Output High Voltage, VOH High Impedance Output Capacitance High Impedance Leakage Current POWER REQUIREMENTS AVDD AVSS DVCC Input Voltage AIDD Min 2 −1 5 0.8 +1 Typ Max Unit V V μA pF Test Conditions/Comments JEDEC compliant Per pin Per pin 0.4 0.6 3.6 0.5 DVCC − 0.5 −1 12 −12 2.7 4.4 5.2 5.2 2.0 2.5 2.5 0.3 108 0.5 DVCC − 0.5 3 +1 24 −24 5.5 5.2 6.2 6.2 2.5 3 3 1 V V V V V pF μA V V V mA mA mA mA mA mA mA mW 10 kΩ pull-up resistor to DVCC @ 2.5 mA 10 kΩ pull-up resistor to DVCC Sinking 200 μA Sourcing 200 μA ±10% ±10% AISS DICC Power Dissipation 1 2 Output unloaded, output disabled Current output enabled Voltage output enabled Output unloaded, output disabled Current output enabled Voltage output enabled VIH = DVCC, VIL = GND AVDD/AVSS = ±24 V, outputs unloaded Temperature range: −40°C to +105°C; typical at +25°C. Specification includes gain and offset errors over temperature, and drift after 1000 hours, TA = 125°C 3 Guaranteed by characterization, but not production tested. Rev. A | Page 7 of 36 AD5750/AD5750-1 TIMING CHARACTERISTICS AVDD/AVSS = ±12 V (± 10%) to ±24 V (± 10%), DVCC = 2.7 V to 5.5 V, GND = 0 V. VOUT: RLOAD = 2 kΩ, CL = 200 pF, IOUT: RLOAD = 300 Ω. All specifications TMIN to TMAX, unless otherwise noted. Table 3. Parameter 1, 2 t1 t2 t3 t4 t5 t6 t7 t8 t9, t10 t11 t12 t13 1 2 Limit at TMIN, TMAX 20 8 8 5 10 5 5 5 1.5 5 40 10 Unit ns min ns min ns min ns min ns min ns min ns min ns min μs max ns min ns max ns min Description SCLK cycle time SCLK high time SCLK low time SYNC falling edge to SCLK falling edge setup time 16th SCLK falling edge to SYNC rising edge (on 24th SCLK falling edge if using PEC) Minimum SYNC high time (write mode) Data setup time Data hold time CLEAR pulse low/high activation time Minimum SYNC high time (read mode) SCLK rising edge to SDO valid (SDO CL = 15 pF) RESET pulse low time Guaranteed by characterization, but not production tested. All input signals are specified with tR = tF = 5 ns (10% to 90% of DVCC) and timed from a voltage level of 1.2 V. Rev. A | Page 8 of 36 AD5750/AD5750-1 Timing Diagrams t1 SCLK 1 2 16 t6 t4 SYNC t3 t2 t5 t8 t7 SDIN D15 D0 CLEAR t10 t9 VOUT RESET t13 Figure 2. Write Mode Timing Diagram 1 SCLK 2 16 SYNC t11 SDIN A2 A1 A0 R=1 0 X X X X X X X X X X X t12 SDO X X X X X R3 R2 R1 R0 CLRSEL OUTEN RSET 07268-004 PEC ERROR OVER TEMP IOUT FAULT VOUT FAULT Figure 3. Readback Mode Timing Diagram Rev. A | Page 9 of 36 07268-003 AD5750/AD5750-1 ABSOLUTE MAXIMUM RATINGS TA = 25°C, unless otherwise noted. Transient currents of up to 100 mA do not cause SCR latch-up. Table 4. Parameter AVDD to GND AVSS to GND AVDD to AVSS DVCC to GND VSENSE+ to GND VSENSE− to GND Digital Inputs to GND Digital Outputs to GND VREF to GND VIN to GND VOUT, IOUT to GND Operating Temperature Range, Industrial Storage Temperature Range Junction Temperature (TJ max) 32-Lead LFCSP Package θJA Thermal Impedance Lead Temperature Soldering ESD (Human Body Model) Rating −0.3 V to +30 V +0.3 V to −28 V −0.3 V to +58 V −0.3 V to +7 V AVSS to AVDD ±5.0 V −0.3 V to DVCC + 0.3 V or 7 V (whichever is less) −0.3 V to DVCC + 0.3 V or 7 V (whichever is less) −0.3 V to +7 V −0.3 V to +7 V AVSS to AVDD −40°C to +105°C −65°C to +150°C 125°C 28°C/W JEDEC industry standard J-STD-020 3 kV Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ESD CAUTION Rev. A | Page 10 of 36 AD5750/AD5750-1 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS NC/IFAULT FAULT/TEMP RESET HW SELECT NC NC NC NC 32 31 30 29 28 27 26 25 PIN 1 INDICATOR SDO/VFAULT CLRSEL CLEAR DVCC GND SYNC/RSET SCLK/OUTEN SDIN/R0 1 2 3 4 5 6 7 8 AD5750/ AD5750-1 TOP VIEW (Not to Scale) 24 23 22 21 20 19 18 17 VSENSE+ VOUT VSENSE– AVSS COMP1 COMP2 IOUT AVDD AD2/R1 AD1/R2 AD0/R3 REXT2 REXT1 VREF VI N GND 9 10 11 12 13 14 15 16 NOTES 1. NC = NO CONNECT. 2. THE EXPOSED PADDLE IS TIED TO AVSS. Figure 4. Pin Configuration Table 5. Pin Function Descriptions Pin No. 1 Mnemonic SDO/VFAULT Description Serial Data Output (SDO). In software mode, this pin is used to clock data from the input shift register in readback mode. Data is clocked out on the rising edge of SCLK and is valid on the falling edge of SCLK. This pin is a CMOS output. Short-Circuit Fault Alert (VFAULT). In hardware mode, this pin acts as a short-circuit fault alert pin and is asserted low when a short-circuit error is detected. This pin is an open-drain output and must be connected to a pull-up resistor. In hardware or software mode, this pin selects the clear value, either zero-scale or midscale code. In software mode, this pin is implemented as a logic OR with the internal CLRSEL bit. Active High Input. Asserting this pin sets the output current/voltage to zero-scale code or midscale code of the range selected (user-selectable). CLEAR is a logic OR with the internal clear bit. In software mode, during power-up, the CLEAR pin level determines the power-on condition of the voltage channel, which can be active 0 V or tristate. See the Asynchronous Clear (CLEAR) section for more details. Digital Power Supply. Ground Connection. Positive Edge-Sensitive Latch (SYNC). In software mode, a rising edge parallel loads the input shift register data into the AD5750, also updating the output. Resistor Select (RSET). In hardware mode, this pin selects whether the internal or the external current sense resistor is used. If RSET = 0, the external sense resistor is chosen. If RSET = 1, the internal sense Resistor is chosen. Serial Clock Input (SCLK). In software mode, data is clocked into the input shift register on the falling edge of SCLK. This pin operates at clock speeds up to 50 MHz. Output Enable (OUTEN). In hardware mode, this pin acts as an output enable pin. Serial Data Input (SDIN). In software mode, data must be valid on the falling edge of SCLK. Range Decode Bit (R0). In hardware mode, this pin, in conjunction with R1, R2, and R3, selects the output current/voltage range setting on the part. Device Addressing Bit (AD2). In software mode, this pin, in conjunction with AD1 and AD0, allows up to eight devices to be addressed on one bus. Range Decode Bit (R1). In hardware mode, this pin, in conjunction with R0, R2, and R3, selects the output current/voltage range setting on the part. Device Addressing Bit (AD1). In software mode, this pin, in conjunction with AD2 and AD0, allows up to eight devices to be addressed on one bus. Range Decode Bit (R2). In hardware mode, this pin, in conjunction with R0, R1, and R3, selects the output current/voltage range setting on the part. Rev. A | Page 11 of 36 2 3 CLRSEL CLEAR 4 5 6 DVCC GND SYNC/RSET 7 SCLK/OUTEN 8 SDIN/R0 9 AD2/R1 10 AD1/R2 07268-005 AD5750/AD5750-1 Pin No. 11 Mnemonic AD0/R3 Description Device Addressing Bit (AD0). In software mode, this pin, in conjunction with AD1 and AD2, allows up to eight devices to be addressed on one bus. Range Decode Bit (R3). In hardware mode, this pin, in conjunction with, R0, R1, and R2, selects the output current/voltage range setting on the part. A 15 kΩ external current setting resistor can be connected between the REXT1 and REXT2 pins to improve the IOUT temperature drift performance. Buffered Reference Input. Buffered Analog Input (0 V to 4.096 V). Ground Connection. Positive Analog Supply. Current Output. Optional Compensation Capacitor Connections for the Voltage Output Buffer. These are used to drive higher capacitive loads on the output. These pins also reduce overshoot on the output. Care should be taken when choosing the value of the capacitor connected between the COMP1 and COMP2 pins because it has a direct influence on the settling time of the output. See the Driving Large Capacitive Loads section for further details. Negative Analog Supply. Sense Connection for the Negative Voltage Output Load Connection. This pin must stay within ±3.0 V of ground for correct operation. Buffered Analog Output Voltage. Sense Connection for the Positive Voltage Output Load Connection. No Connect. Can be tied to GND. This pin is used to configure the part to hardware or software mode. HW SELECT = 0 selects software control. HW SELECT = 1 selects hardware control. Resets the part to its power-on state. Fault Alert (FAULT). In software mode, this pin acts as a general fault alert pin. It is asserted low when an opencircuit error, short-circuit error, overtemperature error, or PEC interface error is detected. This pin is an opendrain output and must be connected to a pull-up resistor. Overtemperature Fault (TEMP). In hardware mode, this pin acts as an overtemperature fault pin. It is asserted low when an overtemperature error is detected. This pin is an open-drain output and must be connected to a pull-up resistor. No Connect (NC). In software mode, this pin is a no connect. Instead, tie this pin to GND. Open-Circuit Fault Alert (IFAULT). In hardware mode, this pin acts as an open-circuit fault alert pin. It is asserted low when an open-circuit error is detected. This pin is an open-drain output and must be connected to a pullup resistor. The exposed paddle is tied to AVSS. 12, 13 14 15 16 17 18 19, 20 REXT2, REXT1 VREF VIN GND AVDD IOUT COMP2, COMP1 21 22 23 24 25, 26, 27, 28 29 AVSS VSENSE− VOUT VSENSE+ NC HW SELECT 30 31 RESET FAULT/TEMP 32 NC/IFAULT 33 (EPAD) Exposed paddle Rev. A | Page 12 of 36 AD5750/AD5750-1 TYPICAL PERFORMANCE CHARACTERISTICS VOLTAGE OUTPUT 0.0020 INTEGRAL NONLINEARITY ERROR (%FSR) AVDD = +24V 0.0015 AVSS = –24V 0.0010 0.0005 0 –0.0005 –0.0010 –0.0015 –0.0020 –0.0025 –0.0030 0 +5V +10V ±5V ±10V 07268-105 0.10 0.08 0.06 0.04 TUE (%FSR) 0.02 0 –0.02 –0.04 –0.06 –0.08 –0.10 +5V POSITIVE TUE, NO LOAD +10V POSITIVE TUE, NO LOAD ±5V POSITIVE TUE, NO LOAD ±10V POSITIVE TUE, NO LOAD +5V NEGATIVE TUE, NO LOAD +10V NEGATIVE TUE, NO LOAD ±5V NEGATIVE TUE, NO LOAD ±10V NEGATIVE TUE, NO LOAD –40 25 TEMPERATURE (°C) 105 07268-108 07268-110 07268-109 0.585 1.170 1.755 2.341 2.926 3.511 4.096 VIN (V) Figure 5. Integral Nonlinearity Error vs. VIN 0.005 INTEGRAL NONLINEARITY ERROR (%FSR) Figure 8. Total Unadjusted Error vs. Temperature 0.03 0.02 FULL-SCALE ERROR (%FSR) AVDD = +24V 0.004 AVSS = –24V 0.003 0.002 0.001 0 –0.001 –0.002 –0.003 –0.004 +5V LINEARITY, NO LOAD +10V LINEARITY, NO LOAD ±5V LINEARITY, NO LOAD ±10V LINEARITY, NO LOAD 0.01 0 –0.01 –0.02 –0.03 +5V RANGE, FULL-SCALE ERROR +10V RANGE, FULL-SCALE ERROR ±5V RANGE, FULL-SCALE ERROR ±10V RANGE, FULL-SCALE ERROR –40 25 TEMPERATURE (°C) 105 –40 25 TEMPERATURE (°C) 105 Figure 6. Integral Nonlinearity Error vs. Temperature 0.006 0.004 0.002 0 –0.002 –0.004 –0.006 –0.008 –0.010 0 0.585 1.170 1.755 2.341 2.926 3.511 4.096 VIN (V) 2.5 2.0 BIPOLAR ZERO ERROR (mV) 07268-106 –0.005 –0.04 Figure 9. Full-Scale Error vs. Temperature AVDD = +24V AVSS = –24V AVDD = +24V AVSS = –24V 1.5 1.0 ±10V ZERO ERROR 0.5 0 –0.5 –1.0 –1.5 ±5V ZERO ERROR –2.0 –2.5 –40 25 TEMPERATURE (°C) 105 TUE (%FSR) +5V +10V ±5V ±10V 07268-107 Figure 7. Total Unadjusted Error vs. VIN Figure 10. Bipolar Zero Error vs. Temperature Rev. A | Page 13 of 36 AD5750/AD5750-1 0.020 0.015 0.010 GAIN ERROR (%FSR) AVDD = +24V AVSS = –24V 0.10 0.08 0.06 0.04 TUE (%FSR) 0.005 0 –0.005 –0.010 –0.015 –0.020 –0.025 +5V GAIN, NO LOAD +10V GAIN, NO LOAD ±5V GAIN, NO LOAD ±10V GAIN, NO LOAD 07268-111 0.02 0 –0.02 –0.04 –0.06 –0.08 +5V POSITIVE TUE, NO LOAD +10V POSITIVE TUE, NO LOAD ±5V POSITIVE TUE, NO LOAD ±10V POSITIVE TUE, NO LOAD +5V NEGATIVE TUE, NO LOAD +10V NEGATIVE TUE, NO LOAD ±5V NEGATIVE TUE, NO LOAD ±10V NEGATIVE TUE, NO LOAD –40 25 TEMPERATURE (°C) 105 +11.2/–10.8 ±15.0 ±24.0 ±26.4 SUPPLY VOLTAGES (AVDD/AVSS) Figure 11. Gain Error vs. Temperature 2.5 AVDD = +24V 2.0 AVSS = –24V OUTPUT UNLOADED 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 –2.5 –3.0 +5V RANGE +10V RANGE ±5V RANGE ±10V RANGE 07268-112 Figure 14. Total Unadjusted Error vs. Supply Voltages 1.2 1.0 ZERO-SCALE ERROR (mV) HEADROOM (V) 0.8 ±10V VDD HEADROOM, LOAD OFF 0.6 0.4 0.2 –40 25 TEMPERATURE (°C) 105 –40 25 TEMPERATURE (°C) 105 Figure 12. Zero-Scale Error (Offset Error) vs. Temperature 0.003 INTEGRAL NONLINEARITY ERROR (%FSR) Figure 15. AVDD Headroom, ±10 V Range, Output Set to 10 V, Load Off 0.05 0.04 OUTPUT VOLTAGE DELTA (V) 0.002 +5V LINEARITY, NO LOAD +10V LINEARITY, NO LOAD ±5V LINEARITY, NO LOAD ±10V LINEARITY, NO LOAD +5V RANGE ±10V RANGE 0.03 0.02 0.01 0 –0.01 –0.02 –0.03 –0.04 0.001 0 –0.001 –0.002 +11.2/–10.8 ±15.0 ±24.0 ±26.4 07268-113 –15 –13 –11 –9 –7 –5 –3 –1 1 3 5 7 9 11 13 15 SUPPLY VOLTAGES (AVDD/AVSS) SOURCE/SINK CURRENT (mA) Figure 13. Integral Nonlinearity Error vs. Supply Voltage Figure 16. Source and Sink Capability of Output Amplifier Rev. A | Page 14 of 36 07268-116 –0.003 –0.05 07268-115 0 07268-114 –0.10 AD5750/AD5750-1 12 10 1 8 VOLTAGE (V) 6 4 2 2 07268-120 07268-122 07268-121 07268-117 0 –8 –3 2 7 12 TIME (µs) 17 22 27 CH1 5.00V CH2 20.0mV BW M1.0µs A CH1 3.00V Figure 17. Full-Scale Positive Step 12 Figure 20. VOUT Enable Glitch, Load = 2 kΩ || 1 nF 10 8 VOLTAGE (V) 6 4 2 5µV/DIV 1s/DIV –3 2 7 12 TIME (µs) 17 22 27 Figure 18. Full-Scale Negative Step 40 35 30 25 VOUT (mV) 07268-118 0 –8 Figure 21. Peak-to-Peak Noise (0.1 Hz to 10 Hz Bandwidth) 20 15 10 5 0 100µV/DIV 1s/DIV 07268-119 –5 –1.0 –0.5 0 0.5 1.0 1.5 2.0 2.5 TIME (ms) Figure 19. VOUT vs. Time on Power-Up, Load = 2 kΩ || 200 pF Figure 22. Peak-to-Peak Noise (100 kHz Bandwidth) Rev. A | Page 15 of 36 AD5750/AD5750-1 4.0 3.5 0.8 3.0 VDD 2.5 2.0 1.5 0.2 1.0 VOUT 0.5 0 –1.5 –0.2 2.0 0 0.4 0.6 1.0 VOUT (V) VDD (V) –1.0 –0.5 0 0.5 1.0 1.5 TIME (ms) Figure 23. VDD and VOUT vs. Time on Power-Up Rev. A | Page 16 of 36 07268-123 AD5750/AD5750-1 CURRENT OUTPUT 0.004 AVDD = +24V AVSS = –24V 0.010 +4mA TO +20mA INTERNAL RSET LINEARITY 0mA TO +20mA INTERNAL R SET LINEARITY 0mA TO +24mA INTERNAL R SET LINEARITY ±20mA INTERNAL R SET LINEARITY ±24mA INTERNAL R SET LINEARITY INTEGRAL NONLINEARITY ERROR (%FSR) INTEGRAL NONLINEARITY ERROR (%FSR) 0.008 0.006 0.004 0.002 0 –0.002 –0.004 –0.006 –0.008 0.002 0 –0.002 –0.004 –0.006 –0.008 –0.010 0 +4mA TO +20mA 0mA TO +20mA 0mA TO +24mA ±20mA ±24mA 07268-124 0.585 1.170 1.755 2.341 2.926 3.511 4.096 +11.2/–10.8 ±15.0 ±24.0 ±26.4 VIN (V) SUPPLY VOLTAGES (AVDD/AVSS) Figure 24. Integral Nonlinearity Error vs. VIN, External RSET Resistor 0.004 0.010 0.008 0.006 0.004 Figure 27. Integral Nonlinearity Error, Current Mode, Internal RSET Sense Resistor AVDD = +24V AVSS = –24V +4mA TO +20mA 0mA TO +20mA 0mA TO +24mA ±20mA ±24mA INTEGRAL NONLINEARITY ERROR (%FSR) 0.002 0 –0.002 AVDD = +24V AVSS = –24V TUE (%FSR) –0.004 –0.006 –0.008 –0.010 –0.012 0 +4mA TO +20mA 0mA TO +20mA 0mA TO +24mA ±20mA ±24mA 0.002 0 –0.002 –0.004 –0.006 0 0.585 1.170 1.755 2.341 2.926 3.511 4.096 VIN (V) VIN (V) Figure 25. Integral Nonlinearity Error vs. VIN, Internal RSET Resistor 0.010 Figure 28. Total Unadjusted Error vs. VIN, External RSET Resistor 0.015 INTEGRAL NONLINEARITY ERROR (%FSR) 0.008 0.006 0.004 0.002 0 –0.002 –0.004 –0.006 +4mA TO +20mA EXTERNAL R SET LINEARITY 0mA TO +20mA EXTERNAL R SET LINEARITY 0mA TO +24mA EXTERNAL R SET LINEARITY ±20mA EXTERNAL R SET LINEARITY ±24mA EXTERNAL R SET LINEARITY AVDD = +24V AVSS = –24V 0.010 +4mA TO +20mA 0mA TO +20mA 0mA TO +24mA ±20mA ±24mA 0.005 TUE (%FSR) 0 –0.005 –0.010 –0.008 +11.2/–10.8 ±15.0 ±24.0 ±26.4 07268-126 –0.010 0 0.585 1.170 1.755 2.341 2.926 3.511 4.096 SUPPLY VOLTAGES (AVDD/AVSS) VIN (V) Figure 26. Integral Nonlinearity Error, Current Mode, External RSET Sense Resistor Figure 29. Total Unadjusted Error vs. VIN, Internal RSET Resistor Rev. A | Page 17 of 36 07268-129 –0.015 07268-128 0.585 1.170 1.755 2.341 2.926 3.511 4.096 07268-125 –0.008 07268-127 –0.010 AD5750/AD5750-1 0.10 0.08 0.06 0.04 +4mA TO +20mA EXTERNAL R SET POSITIVE TUE 0mA TO +20mA EXTERNAL RSET POSITIVE TUE 0mA TO +24mA EXTERNAL RSET POSITIVE TUE ±20mA EXTERNAL R SET POSITIVE TUE ±24mA EXTERNAL R SET POSITIVE TUE 0.010 0.008 0.006 +4mA TO +20mA EXTERNAL R SET LINEARITY 0mA TO +20mA EXTERNAL RSET LINEARITY 0mA TO +24mA EXTERNAL RSET LINEARITY ±20mA EXTERNAL R SET LINEARITY ±24mA EXTERNAL R SET LINEARITY 0.02 0 –0.02 –0.04 –0.06 –0.08 –0.10 +4mA TO +20mA EXTERNAL R SET NEGATIVE TUE 0mA TO +20mA EXTERNAL RSET NEGATIVE TUE 0mA TO +24mA EXTERNAL RSET NEGATIVE TUE ±20mA EXTERNAL R SET NEGATIVE TUE ±24mA EXTERNAL R SET NEGATIVE TUE +11.2/–10.8 ±15.0 ±24.0 ±26.4 07268-130 LINEARITY (%FSR) 0.004 0.002 0 –0.002 –0.004 –0.006 –0.008 AVDD = +24V AVSS = –24V –0.010 –40 TUE (%FSR) 25 TEMPERATURE (°C) 105 SUPPLY VOLTAGES (AVDD/AVSS) Figure 30. Total Unadjusted Error Current Mode, External RSET Sense Resistor 0.10 0.08 0.06 0.04 +4mA TO +20mA INTERNAL RSET POSITIVE TUE 0mA TO +20mA INTERNAL R SET POSITIVE TUE 0mA TO +24mA INTERNAL R SET POSITIVE TUE ±20mA INTERNAL R SET POSITIVE TUE ±24mA INTERNAL R SET POSITIVE TUE Figure 33. INL vs. Temperature, External RSET Sense Resistor 0.10 0.08 0.06 0.04 +4mA TO +20mA INTERNAL RSET POSITIVE TUE 0mA TO +20mA INTERNAL RSET POSITIVE TUE 0mA TO +24mA INTERNAL RSET POSITIVE TUE ±20mA INTERNAL R SET POSITIVE TUE ±24mA INTERNAL R SET POSITIVE TUE TUE (%FSR) TUE (%FSR) 0.02 0 –0.02 –0.04 –0.06 –0.08 –0.10 +4mA TO +20mA INTERNAL RSET NEGATIVE TUE 0mA TO +20mA INTERNAL R SET NEGATIVE TUE 0mA TO +24mA INTERNAL R SET NEGATIVE TUE ±20mA INTERNAL R SET NEGATIVE TUE ±24mA INTERNAL R SET NEGATIVE TUE +11.2/–10.8 ±15.0 ±24.0 ±26.4 07268-131 0.02 0 –0.02 –0.04 –0.06 –0.08 –0.10 +4mA TO +20mA INTERNAL RSET NEGATIVE TUE 0mA TO +20mA INTERNAL RSET NEGATIVE TUE 0mA TO +24mA INTERNAL RSET NEGATIVE TUE ±20mA INTERNAL R SET NEGATIVE TUE ±24mA INTERNAL R SET NEGATIVE TUE –40 25 TEMPERATURE (°C) 105 SUPPLY VOLTAGES (AVDD/AVSS) Figure 31. Total Unadjusted Error Current Mode, Internal RSET Sense Resistor 0.010 0.008 0.006 +4mA TO +20mA INTERNAL RSET LINEARITY 0mA TO +20mA INTERNAL R SET LINEARITY 0mA TO +24mA INTERNAL R SET LINEARITY ±20mA INTERNAL R SET LINEARITY ±24mA INTERNAL R SET LINEARITY Figure 34. Total Unadjusted Error vs. Temperature, Internal RSET Sense Resistor 0.10 0.08 0.06 0.04 +4mA TO +20mA EXTERNAL R SET POSITIVE TUE 0mA TO +20mA EXTERNAL R SET POSITIVE TUE 0mA TO +24mA EXTERNAL R SET POSITIVE TUE ±20mA EXTERNAL R SET POSITIVE TUE ±24mA EXTERNAL R SET POSITIVE TUE LINEARITY (%FSR) 0.004 TUE (%FSR) 0.002 0 –0.002 –0.004 –0.006 –0.008 AVDD = +24V AVSS = –24V –0.010 –40 0.02 0 –0.02 –0.04 –0.06 –0.08 +4mA TO +20mA EXTERNAL R SET NEGATIVE TUE 0mA TO +20mA EXTERNAL R SET NEGATIVE TUE 0mA TO +24mA EXTERNAL R SET NEGATIVE TUE ±20mA EXTERNAL R SET NEGATIVE TUE ±24mA EXTERNAL R SET NEGATIVE TUE 07268-132 25 TEMPERATURE (°C) 105 –40 25 TEMPERATURE (°C) 105 Figure 32. INL vs. Temperature, Internal RSET Sense Resistor Figure 35. Total Unadjusted Error vs. Temperature, External RSET Sense Resistor Rev. A | Page 18 of 36 07268-135 –0.10 07268-134 07268-133 AD5750/AD5750-1 6 AVDD = +24V AVSS = –24V 4 BIPOLAR ZERO-SCALE ERROR (µA) +4mA TO +20mA EXTERNAL R SET 0mA TO +20mA EXTERNAL R SET 0mA TO +24mA EXTERNAL R SET 2 1 0 ±20mA, INTERNAL R SET –1 –2 ±24mA, INTERNAL R SET –3 –4 –5 –6 ZERO-SCALE ERROR (µA) 2 0 –2 –4 ±20mA EXTERNAL R SET ±24mA EXTERNAL R SET 07268-136 –40 25 TEMPERATURE (°C) 105 –40 25 TEMPERATURE (°C) 105 Figure 36. Zero-Scale Error vs. Temperature, External RSET Sense Resistor 25 20 0.04 0.03 Figure 39. Bipolar Zero-Scale Error vs. Temperature, Internal RSET Sense Resistor +4mA TO +20mA EXTERNAL R SET 0mA TO +20mA EXTERNAL R SET 0mA TO +24mA EXTERNAL R SET +4mA TO +20mA INTERNAL R SET 0mA TO +20mA INTERNAL RSET 0mA TO +24mA INTERNAL RSET FULL-SCALE ERROR (%FSR) ZERO-SCALE ERROR (µA) 15 10 AVDD = +24V AVSS = –24V 5 0 –5 –10 –15 –20 ±20mA INTERNAL R SET ±24mA INTERNAL R SET 07268-137 0.02 AVDD = +24V 0.01 AVSS = –24V 0 –0.01 –0.02 –0.03 –0.04 ±20mA EXTERNAL R SET ±24mA EXTERNAL R SET –40 25 TEMPERATURE (°C) 105 07268-140 07268-141 –40 25 TEMPERATURE (°C) 105 Figure 37. Zero-Scale Error vs. Temperature, Internal RSET Sense Resistor 3 2 1 ±24mA, EXTERNAL R SET 0 –1 –2 ±20mA, EXTERNAL R SET –3 –4 –5 Figure 40. Full-Scale Error vs. Temperature, External RSET Sense Resistor 0.04 0.03 BIPOLAR ZERO-SCALE ERROR (µA) FULL-SCALE ERROR (%FSR) 0.02 0.01 0 –0.01 –0.02 –0.03 –0.04 –0.05 +4mA TO +20mA INTERNAL R SET 0mA TO +20mA INTERNAL RSET 0mA TO +24mA INTERNAL RSET ±20mA INTERNAL R SET ±24mA INTERNAL R SET AVDD = +24V AVSS = –24V –40 25 TEMPERATURE (°C) 105 07268-138 AVDD = +24V AVSS = –24V –40 25 TEMPERATURE (°C) 105 –0.06 Figure 38. Bipolar Zero-Scale Error vs. Temperature, External RSET Sense Resistor Figure 41. Full-Scale Error vs. Temperature, Internal RSET Sense Resistor Rev. A | Page 19 of 36 07268-139 –6 AVDD = +24V AVSS = –24V AD5750/AD5750-1 0.020 0.015 0.010 0.005 0 –0.005 –0.010 –0.015 AVDD = +24V AVSS = –24V –40 25 TEMPERATURE (°C) ±20mA EXTERNAL R SET ±24mA EXTERNAL R SET 105 07268-142 +4mA TO +20mA EXTERNAL RSET 0mA TO +20mA EXTERNAL R SET 0mA TO +24mA EXTERNAL R SET 12 10 0.000010 0.000008 0.000006 GAIN ERROR (%FSR) 8 6 4 2 0 VDD –2 –10 –8 –6 –4 –2 0 TIME (ms) 2 4 6 8 10 0.000004 0.000002 IOUT 0 –0.000002 –0.000004 –0.000006 –0.000008 07268-145 –0.000010 Figure 42. Gain Error vs. Temperature, External RSET Sense Resistor 0.08 0.06 0.04 +4mA TO +20mA INTERNAL R SET 0mA TO +20mA INTERNAL RSET 0mA TO +24mA INTERNAL RSET ±20mA INTERNAL R SET ±24mA INTERNAL R SET 0 –2 –4 –6 Figure 45. Output Current vs. Time on Power-Up GAIN ERROR (%FSR) 0.02 IOUT (V) 0 –0.02 –0.04 –0.06 –0.08 –0.10 AVDD = +24V AVSS = –24V 07268-143 –8 –10 –12 –14 –16 07268-146 07268-147 –40 25 TEMPERATURE (°C) 105 –18 –2 –1 0 1 2 3 TIME (µs) 4 5 6 7 8 Figure 43. Gain Error vs. Temperature, Internal RSET Sense Resistor 1.4 1.2 AVDD COMPLIANCE 1.0 Figure 46. Output Current vs. Time on Output Enable 0.025 0.020 COMPLIANCE (V) CURRENT (A) 0.8 AVSS COMPLIANCE 0.6 0.4 0.015 0.010 0.005 0.2 0 –40 25 TEMPERATURE (°C) 105 07268-144 0 –12 –6 1 8 14 21 28 34 41 48 54 61 68 TIME (µs) Figure 44. Output Compliance vs. Temperature Tested When IOUT = 10.8 mA, ±24 mA Range Selected Figure 47. 4 mA to 20 mA Output Current Step Rev. A | Page 20 of 36 IOUT (A) VDD (V) AD5750/AD5750-1 3000 6 5 2500 4 AIDD DICC (µA) DVCC = 5V 1500 AIDD/AISS (mA) 2000 3 2 1 0 –1 1000 500 DVCC = 3V 07268-148 –2 –3 ±10.8 ±15.0 AISS ±24.0 ±26.4 07268-150 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 LOGIC LEVEL (V) AVDD/AVSS (V) Figure 48. DICC vs. Logic Input Voltage 6 5 AIDD 4 3 2 1 0 –1 –2 –3 ±10.8 ±15.0 AISS ±24.0 ±26.4 07268-149 Figure 50. AIDD/AISS vs. AVDD/AVSS, IOUT = 0 mA AIDD/AISS (mA) AVDD/AVSS (V) Figure 49. AIDD/AISS vs. AVDD/AVSS, VOUT = 0 V Rev. A | Page 21 of 36 AD5750/AD5750-1 TERMINOLOGY Total Unadjusted Error (TUE) TUE is a measure of the output error taking all the various errors into account: INL error, offset error, gain error, and output drift over supplies, temperature, and time. TUE is expressed as a percentage of full-scale range (% FSR). Relative Accuracy or Integral Nonlinearity (INL) INL is a measure of the maximum deviation, in % FSR, from a straight line passing through the endpoints of the output driver transfer function. A typical INL vs. input voltage plot can be seen in Figure 5. Bipolar Zero Error Bipolar zero error is the deviation of the actual vs. ideal halfscale output of 0 V/0 mA with a bipolar range selected. A plot of bipolar zero error vs. temperature can be seen in Figure 10. Bipolar Zero TC Bipolar zero TC is a measure of the change in the bipolar zero error with a change in temperature. It is expressed in ppm FSR/°C. Full-Scale Error Full-scale error is the deviation of the actual full-scale analog output from the ideal full-scale output. Full-scale error is expressed as a percentage of full-scale range (% FSR). Full-Scale TC Full-scale TC is a measure of the change in the full-scale error with a change in temperature. It is expressed in ppm FSR/°C. Gain Error Gain error is a measure of the span error of the output. It is the deviation in slope of the output transfer characteristic from the ideal expressed in % FSR. A plot of gain error vs. temperature can be seen in Figure 11. Gain Error TC Gain error TC is a measure of the change in gain error with changes in temperature. Gain error TC is expressed in ppm FSR/°C. Zero-Scale Error Zero-scale error is the deviation of the actual zero-scale analog output from the ideal zero-scale output. Zero-scale error is expressed in millivolts (mV). Zero-Scale TC Zero-scale TC is a measure of the change in zero-scale error with a change in temperature. Zero-scale error TC is expressed in ppm FSR/°C. Offset Error Offset error is a measurement of the difference between the actual VOUT and the ideal VOUT, expressed in millivolts (mV) in the linear region of the transfer function. It can be negative or positive. Output Voltage Settling Time Output voltage settling time is the amount of time it takes for the output to settle to a specified level for a half-scale input change. Slew Rate The slew rate of a device is a limitation in the rate of change of the output voltage. The output slewing speed is usually limited by the slew rate of the amplifier used at its output. Slew rate is measured from 10% to 90% of the output signal and is expressed in V/μs. Current Loop Voltage Compliance Current loop voltage compliance is the maximum voltage at the IOUT pin for which the output current is equal to the programmed value. Power-On Glitch Energy Power-on glitch energy is the impulse injected into the analog output when the AD5750/AD5750-1 are powered on. It is specified as the area of the glitch in nV-sec. Power Supply Rejection Ratio (PSRR) PSRR indicates how the output is affected by changes in the power supply voltage. Rev. A | Page 22 of 36 AD5750/AD5750-1 THEORY OF OPERATION The AD5750/AD5750-1 are single-channel, precision voltage/ current output drivers with hardware- or software-programmable output ranges. The software ranges are configured via an SPI-/ MICROWIRE-compatible serial interface. The analog input to the AD5750/AD5750-1 is provided from a low voltage, singlesupply digital-to-analog converter (DAC) and is internally conditioned to provide the desired output current/voltage range. Analog input ranges available are 0 V to 2.5 V (AD5750-1) or 0 V to 4.096 V (AD5750). The output current range is programmable across five current ranges: 4 mA to 20 mA, 0 mA to 20 mA or 0 mA to 24 mA, ±20 mA, and ±24 mA. The voltage output is provided from a separate pin that can be configured to provide 0 V to 5 V, 0 V to 10 V, ±5 V, or ±10 V output ranges. An overrange of 20% is available on the voltage ranges. An overrange of 2% is available on the 4 mA to 20 mA, 0 mA to 20 mA, and 0 mA to 24 mA current ranges. The current and voltage outputs are available on separate pins. Only one output can be enabled at one time. The output range is selected by programming the R3 to R0 bits in the control register (see Table 7 and Table 8). Figure 51 and Figure 52 show a typical configuration of the AD5750/AD5750-1 in software mode and in hardware mode, respectively, in an output module system. The HW SELECT pin selects whether the part is configured in software or hardware mode. The analog input to the AD5750/AD5750-1 is provided from a low voltage, single-supply DAC such as the AD506x or AD566x, which provides an output range of 0 V to 4.096 V. The supply and reference for the DAC, as well as the reference for the AD5750/AD5750-1, can be supplied from a reference such as the ADR392. The AD5750/AD5750-1 can operate from supplies up to ±26.4 V. SOFTWARE MODE In current mode, software-selectable output ranges include ±20 mA, ±24 mA, 0 mA to 20 mA, 4 mA to 20 mA, and 0 mA to 24 mA. In voltage mode, software-selectable output ranges include 0 V to 5 V, 0 V to 10 V, ±5 V, and ±10 V. VDD AGND VSS ADP1720 ADR392 SCLK SDI/DIN MCU SDO SYNC1 VDD REFIN VREF AVDD GND AVSS AD5750/AD5750-1 VOUT RANGE SCALE VIN IOUT RANGE SCALE SCLK SDIN SDO SYNC HW SELECT SERIAL INTERFACE VSENSE+ VSENSE– VOUT 0V TO +5V, 0V TO +10V, ±5V, ±10V AD506x AD566x VOUT SHORT FAULT IOUT OPEN FAULT OVERTEMP FAULT STATUS REGISTER IOUT 0mA TO +20mA, 0mA TO +24mA, +4mA TO +20mA, ±20mA, ±24mA FAULT Figure 51. Typical System Configuration in Software Mode (Pull-Up Resistors Not Shown for Open-Drain Outputs) Rev. A | Page 23 of 36 07268-045 AD5750/AD5750-1 VDD AGND VSS ADP1720 ADR392 SCLK SDI/DIN MCU SDO SYNC1 VDD REFIN VIN VREF AVDD GND AVSS VSENSE+ VSENSE– AD5750/AD5750-1 VOUT RANGE SCALE VOUT 0V TO +5V, 0V TO +10V, ±5V, ±10V AD506x AD566x IOUT RANGE SCALE DVCC HW SELECT OUTEN IOUT 0mA TO +20mA, 0mA TO +24mA, +4mA TO +20mA, ±20mA, ±24mA R3 R2 R1 OUTPUT RANGE SELECT PINS TEMP VFAULT IFAULT R0 07268-046 Figure 52. Typical System Configuration in Hardware Mode Using Internal DAC Reference (Pull-Up Resistors Not Shown for Open-Drain Outputs) Table 6. Suggested Parts for Use with AD5750 and AD5750-1 DAC AD5660 AD5664R AD5668 AD5060 AD5064 AD5662 AD5664 1 2 Reference Internal Internal Internal ADR434 ADR434 ADR392 2 ADR3922 Power ADP1720 1 N/A N/A ADP1720 N/A ADR3922 N/A Accuracy 12-bit INL N/A N/A 16-bit INL N/A 12-bit INL N/A Description Mid end system, single channel, internal reference Mid end system, quad channel, internal reference Mid end system, octal channel, internal reference High end system, single channel, external reference High end system, quad channel, external reference Mid end system, single channel, external reference Mid end system, quad channel, external reference ADP1720 input range up to 28 V. ADR392 input range up to 15 V. Rev. A | Page 24 of 36 AD5750/AD5750-1 CURRENT OUTPUT ARCHITECTURE The voltage input from the analog input VIN pin (0 V to 4.096 V for AD5750; 0 V to 2.5 V for the AD5750-1) is either converted to a current (see Figure 53), which is then mirrored to the supply rail so that the application simply sees a current source output with respect to an internal reference voltage, or it is buffered and scaled to output a software-selectable unipolar or bipolar voltage range (see Figure 54). The reference is used to provide internal offsets for range and gain scaling. The selectable output range is programmable through the digital interface. RANGE DECODE FROM INTERFACE R2 VDD R3 The current and voltage are output on separate pins and cannot be output simultaneously. This allows the user to tie both the current and voltage output pins together and configure the end system as a single-channel output. Driving Large Capacitive Loads The voltage output amplifier is capable of driving capacitive loads of up to 1 μF with the addition of a nonpolarized compensation capacitor between the COMP1 and COMP2 pins. Without the compensation capacitor, up to 20 nF capacitive loads can be driven. Care should be taken to choose an appropriate value for the CCOMP capacitor. This capacitor, while allowing the AD5750/AD5750-1 to drive higher capacitive loads and reduce overshoot, increases the settling time of the part and therefore affects the bandwidth of the system. Considered values of this capacitor should be in the range 100 pF to 4 nF, depending on the trade-off required between settling time, overshoot, and bandwidth. VIN VREF IOUT RANGE SCALING RSET Vx REXT1 REXT2 IOUT POWER-ON STATE OF AD5750/AD5750-1 R1 VSS R4 07268-047 IOUT OPEN FAULT On power-up, the AD5750/AD5750-1 sense whether hardware or software mode is loaded and set the power-up conditions accordingly. In software SPI mode, the power-up state of the output is dependent on the state of the CLEAR pin. If the CLEAR pin is pulled high, then the part powers up, driving an active 0 V on the output. If the CLEAR pin is pulled low, then the part powers up with the voltage output channel in tristate mode. In both cases, the current output channel powers up in the tristate condition (0 mA). This allows the voltage and current outputs to be connected together if desired. To put the part into normal operation, the user must set the OUTEN bit in the control register to enable the output and, in the same write, set the output range configuration using the R3 to R0 range bits. If the CLEAR pin is still high (active) during this write, the part automatically clears to its normal clear state as defined by the programmed range and by the CLRSEL pin or the CLRSEL bit (see the Asynchronous Clear (CLEAR) section for more details). The CLEAR pin must be taken low to operate the part in normal mode. The CLEAR pin is typically driven directly from a microcontroller. In cases where the power supply for the AD5750/AD5750-1 supply may be independent of the microcontroller power supply, the user can connect a weak pull-up resistor to DVCC or a pulldown resistor to ground to ensure that the correct power-up condition is achieved independent of the microcontroller. A 10 kΩ pull-up/pull-down resistor on the CLEAR pin should be sufficient for most applications. If hardware mode is selected, the part powers up to the conditions defined by the R3 to R0 range bits and the status of the OUTEN or CLEAR pin. It is recommended to keep the output disabled when powering up the part in hardware mode. Figure 53. Current Output Configuration RANGE DECODE FROM INTERFACE VSENSE+ VIN (0V TO 4.096V) VREF VOUT RANGE SCALING VOUT SHORT FAULT VSENSE– VOUT Figure 54. Voltage Output DRIVING INDUCTIVE LOADS When driving inductive or poorly defined loads, connect a 0.01 μF capacitor between IOUT and GND. This ensures stability with loads beyond 50 mH. There is no maximum capacitance limit. The capacitive component of the load may cause slower settling. Voltage Output Amplifier The voltage output amplifier is capable of generating both unipolar and bipolar output voltages. It is capable of driving a load of 1 kΩ in parallel with 1.2 μF (with an external compensation capacitor on the COMP1 and COMP2 pins). The source and sink capabilities of the output amplifier can be seen in Figure 16. The slew rate is 2 V/μs. Internal to the device, there is a 2.5 MΩ resistor connected between the VOUT and VSENSE+ pins and similarly between the VSENSE− pin and the internal device ground. Should a fault condition occur, these resistors act to protect the AD5750/ AD5750-1 by ensuring the amplifier loop is closed so that the part does not enter into an open-loop condition. The VSENSE− pin can work in a common-mode range of ±3 V with respect to the remote load ground point. Rev. A | Page 25 of 36 07268-048 AD5750/AD5750-1 DEFAULT REGISTERS AT POWER-ON The AD5750/AD5750-1 power-on reset circuit ensures that all registers are loaded with zero code. In software SPI mode, the part powers up with all outputs disabled (OUTEN bit = 0). The user must set the OUTEN bit in the control register to enable the output and, in the same write, set the output range configuration using the R3 to R0 bits. If hardware mode is selected, the part powers up to the conditions defined by the R3 to R0 bits and the status of the OUTEN pin. It is recommended to keep the output disabled when powering up the part in hardware mode. disabled, both the current and voltage channels go into tristate. The user must set the OUTEN bit to enable the output and simultaneously set the output range configuration. In hardware mode, the output can be enabled or disabled using the OUTEN pin. When the output is disabled, both the current and voltage channels go into tristate. The user must write to the OUTEN pin to enable the output. It is recommended that the output be disabled when changing the ranges. SOFTWARE CONTROL Software control is enabled by connecting the HW SELECT pin to ground. In software mode, the AD5750/AD5750-1 are controlled over a versatile 3-wire serial interface that operates at clock rates up to 50 MHz. It is compatible with SPI, QSPI™, MICROWIRE, and DSP standards. RESET FUNCTION In software mode, the part can be reset using the RESET pin (active low) or the reset bit (reset = 1). A reset disables both the current and voltage outputs to their power-on condition. The user must write to the OUTEN bit to enable the output and, in the same write, set the output range configuration. The RESET pin is a level-sensitive input; the part stays in reset mode as long as the RESET pin is low. The reset bit clears to 0 following a reset command to the control register. In hardware mode, there is no reset. If using the part in hardware mode, the RESET pin should be tied high. Input Shift Register The input shift register is 16 bits wide. Data is loaded into the device MSB first as a 16-bit word under the control of a serial clock input, SCLK. Data is clocked in on the falling edge of SCLK. The input shift register consists of 16 control bits, as shown in Table 7. The timing diagram for this write operation is shown in Figure 2. The first three bits of the input shift register are used to set the hardware address of the AD5750/AD5750-1 device on the printed circuit board (PCB). Up to eight devices can be addressed per board. Bit D11, Bit D1, and Bit D0 must always be set to 0 during any write sequence. OUTEN In software mode, the output can be enabled or disabled using the OUTEN bit in the control register. When the output is Table 7. Input Shift Register Contents for a Write Operation—Control Register MSB D15 A2 D14 A1 D13 A0 D12 R/W D11 0 D10 R3 D9 R2 D8 R1 D7 R0 D6 CLRSEL D5 OUTEN D4 Clear D3 RSET D2 Reset D1 0 LSB D0 0 Table 8. Input Shift Register Descriptions Bit A2, A1, A0 Description Used in association with the AD2, AD1, and AD0 external pins to determine which part is being addressed by the system controller. A2 A1 A0 Function 0 0 0 Addresses part with Pin AD2 = 0, Pin AD1 = 0, Pin AD0 = 0. 0 0 1 Addresses part with Pin AD2 = 0, Pin AD1 = 0, Pin AD0 = 1. 0 1 0 Addresses part with Pin AD2 = 0, Pin AD1 = 1, Pin AD0 = 0. 0 1 1 Addresses part with Pin AD2 = 0, Pin AD1 = 1, Pin AD0 = 1. 1 0 0 Addresses part with Pin AD2 = 1, Pin AD1 = 0, Pin AD0 = 0. 1 0 1 Addresses part with Pin AD2 = 1, Pin AD1 = 0, Pin AD0 = 1. 1 1 0 Addresses part with Pin AD2 = 1, Pin AD1 = 1, Pin AD0 = 0. 1 1 1 Addresses part with Pin AD2 = 1, Pin AD1 = 1, Pin AD0 = 1. Indicates a read from or a write to the addressed register. R/W Rev. A | Page 26 of 36 AD5750/AD5750-1 Bit R3, R2, R1, R0 Description Selects the output configuration in conjunction with RSET. RSET R3 R2 R1 R0 Output Configuration 0 0 0 0 0 4 mA to 20 mA (external 15 kΩ current sense resistor). 0 0 0 0 1 0 mA to 20 mA (external 15 kΩ current sense resistor). 0 0 0 1 0 0 mA to 24 mA (external 15 kΩ current sense resistor). 0 0 0 1 1 ±20 mA (external 15 kΩ current sense resistor). 0 0 1 0 0 ±24 mA (external 15 kΩ current sense resistor). 0 0 1 0 1 0 V to 5 V. 0 0 1 1 0 0 V to 10 V. 0 0 1 1 1 ±5 V. 0 1 0 0 0 ±10 V. 0 1 0 0 1 0 V to 6.0 V (20% overrange). 0 1 0 1 0 0 V to 12.0 V (20% overrange). 0 1 0 1 1 ±6.0 V (20% overrange). 0 1 1 0 0 ±12.0 V (20% overrange). 0 1 1 0 1 ±2.5 V. 0 1 1 1 0 N/A; if selected, output drives between 0 V and −1 V. 0 1 1 1 1 N/A; if selected, output drives between 0 V and −1 V. 1 0 0 0 0 4 mA to 20 mA (internal current sense resistor). 1 0 0 0 1 0 mA to 20 mA (internal current sense resistor). 1 0 0 1 0 0 mA to 24 mA (internal current sense resistor). 1 0 0 1 1 ±20 mA (internal current sense resistor). 1 0 1 0 0 ±24 mA (internal current sense resistor). 1 0 1 0 1 0 V to 5 V. 1 0 1 1 0 0 V to 10 V. 1 0 1 1 1 ±5 V. 1 1 0 0 0 ±10 V. 1 1 0 0 1 0 V to 6.0 V (20% overrange). 1 1 0 1 0 0 V to 12.0 V (20% overrange). 1 1 0 1 1 ±6.0 V (20% overrange). 1 1 1 0 0 ±12.0 V (20% overrange). 1 1 1 0 1 3.92 mA to 20.4 mA (internal current sense resistor). 1 1 1 1 0 0 mA to 20.4 mA (internal current sense resistor). 1 1 1 1 1 0 mA to 24.5 mA (internal current sense resistor). Sets clear mode to zero scale or midscale. See the Asynchronous Clear (CLEAR) section. CLRSEL Function 0 Clear to 0 V. 1 Clear to midscale in unipolar mode; clear to zero scale in bipolar mode. Output enable bit. This bit must be set to 1 to enable the outputs. Software clear bit, active high. Select internal/external current sense resistor. RSET Function 1 Select internal current sense resistor; used with R3 to R0 bits to select range. 0 Select external current sense resistor; used with R3 to R0 bits to select range. Resets the part to its power-on state. CLRSEL OUTEN Clear RSET Reset Rev. A | Page 27 of 36 AD5750/AD5750-1 Readback Operation Readback mode is activated by selecting the correct device address (A2, A1, A0) and then setting the R/W bit to 1. By default, the SDO pin is disabled. After having addressed the AD5750/ AD5750-1 for a read operation, setting R/W to 1 enables the SDO pin and SDO data is clocked out on the 5th rising edge of SCLK. After the data has been clocked out on SDO, a rising edge on SYNC disables (tristate) the SDO pin again. Status register data (see Table 9) and control register data are both available during the same read cycle. The status bits comprise four read-only bits. They are used to notify the user of specific fault conditions that occur, such as an open circuit or short circuit on the output, overtemperature error, or an interface error. If any of these fault conditions occur, a hardware FAULT is also asserted low, which can be used as a hardware interrupt to the controller. See the Detailed Description of Features section for a full explanation of fault conditions. In hardware mode, there is no status register. The fault conditions (open circuit, short circuit, and overtemperature) are available on Pin IFAULT, Pin VFAULT, and Pin TEMP. If any one of these fault conditions are set, then a low is asserted on the specific fault pin. IFAULT, VFAULT, and TEMP are opendrain outputs and therefore can be connected together to allow the user to generate one interrupt to the system controller to communicate a fault. If hardwired in this way, it is not possible to isolate which fault occurred in the system. TRANSFER FUNCTION The AD5750/AD5750-1 consist of an internal signal conditioning block that maps the analog input voltage to a programmed output range. The available analog input ranges are 0 V to 4.096 V (AD5750) and 0 V to 2.5 V (AD5750-1). For all ranges, both current and voltage, the AD5750 and AD5750-1 implement a straight linear mapping function, where 0 V maps to the lower end of the selected range and 4.096 V (or 2.5 V for AD5750-1) maps to the upper end of the selected range. HARDWARE CONTROL Hardware control is enabled by connecting the HW SELECT pin to DVCC. In this mode, the R3, R2, R1, and R0 pins in conjunction with the RSET pin are used to configure the output range, as per Table 8. Table 9. Input Shift Register Contents for a Read Operation—Status Register MSB D15 A2 D14 A1 D13 A0 D12 1 D11 0 D10 R3 D9 R2 D8 R1 D7 R0 D6 CLRSEL D5 OUTEN D4 RSET D3 PEC error D2 OVER TEMP D1 IOUT fault LSB D0 VOUT fault Table 10. Status Bit Options Bit PEC Error OVER TEMP IOUT Fault VOUT Fault Description This bit is set if there is an interface error detected by CRC-8 error checking. See the Detailed Description of Features section. This bit is set if the AD5750/AD5750-1 core temperature exceeds approximately 150°C. This bit is set if there is an open circuit on the IOUT pin. This bit is set if there is a short circuit on the VOUT pin. Rev. A | Page 28 of 36 AD5750/AD5750-1 DETAILED DESCRIPTION OF FEATURES OUTPUT FAULT ALERT—SOFTWARE MODE In software mode, the AD5750/AD5750-1 are equipped with one FAULT pin; this is an open-drain output allowing several AD5750/AD5750-1 devices to be connected together to one pull-up resistor for global fault detection. In software mode, the FAULT pin is forced active low by any one of the following fault scenarios: • The voltage at IOUT attempts to rise above the compliance range due to an open-loop circuit or insufficient power supply voltage. The internal circuitry that develops the fault output avoids using a comparator with window limits because this requires an actual output error before the fault output becomes active. Instead, the signal is generated when the internal amplifier in the output stage has less than approximately 1 V of remaining drive capability. Thus, the fault output activates slightly before the compliance limit is reached. Because the comparison is made within the feedback loop of the output amplifier, the output accuracy is maintained by its open-loop gain, and an output error does not occur before the fault output becomes active. A short is detected on the voltage output pin (VOUT). The short-circuit current is limited to 15 mA. An interface error is detected due to packet error checking (PEC) failure. See the Packet Error Checking section. If the core temperature of the AD5750/AD5750-1 exceeds approximately 150°C. circuitry that develops the fault output avoids using a comparator with window limits because this requires an actual output error before the fault output becomes active. Instead, the signal is generated when the internal amplifier in the output stage has less than approximately 1 V of remaining drive capability. Thus, the fault output activates slightly before the compliance limit is reached. Because the comparison is made within the feedback loop of the output amplifier, the output accuracy is maintained by its openloop gain, and an output error does not occur before the fault output becomes active. If this fault is detected, the IFAULT pin is forced low. A short is detected on the voltage output pin (VOUT). The short-circuit current is limited to 15 mA. If this fault is detected, the VFAULT pin is forced low. The core temperature of the AD5750/AD5750-1 exceeds approximately 150°C. If this fault is detected, the TEMP pin is forced low. • • VOLTAGE OUTPUT SHORT-CIRCUIT PROTECTION Under normal operation, the voltage output sinks and sources up to 12 mA and maintains specified operation. The maximum current that the voltage output delivers is 15 mA; this is the short-circuit current. • • • ASYNCHRONOUS CLEAR (CLEAR) CLEAR is an active high clear that allows the voltage output to be cleared to either zero-scale code or midscale code, and is user-selectable via the CLRSEL pin or the CLRSEL bit of the input shift register, as described in Table 8. (The clear select feature is a logical OR function of the CLRSEL pin and the CLRSEL bit). The current loop output clears to the bottom of its programmed range. When the CLEAR signal is returned low, the output returns to its programmed value or to a new programmed value. A clear operation can also be performed via the clear command in the control register. OUTPUT FAULT ALERT—HARDWARE MODE In hardware mode, the AD5750/AD5750-1 are equipped with three fault pins: VFAULT, IFAULT, and TEMP. These are opendrain outputs allowing several AD5750/AD5750-1 devices to be connected together to one pull-up resistor for global fault detection. In hardware control mode, these fault pins are forced active by any one of the following fault scenarios: • An open circuit is detected. The voltage at IOUT attempts to rise above the compliance range, due to an open-loop circuit or insufficient power supply voltage. The internal Table 11. CLRSEL Options Output Clear Value CLRSEL 0 Unipolar Output Voltage Range 0V Unipolar Current Output Range Zero scale; for example, 4 mA on the 4 mA to 20 mA range 0 mA on the 0 mA to 20 mA range Midscale; for example, 12 mA on the 4 mA to 20 mA range 10 mA on the 0 mA to 20 mA range Bipolar Output Range Negative full scale Bipolar Current Output Range Zero scale; for example, −24 mA on the ±24 mA range Midscale; for example, 0 mA on the ±24 mA range 1 Midscale 0V Rev. A | Page 29 of 36 AD5750/AD5750-1 EXTERNAL CURRENT SETTING RESISTOR Referring to Figure 1, RSET is an internal sense resistor and is part of the voltage-to-current conversion circuitry. The nominal value of the internal current sense resistor is 15 kΩ. To allow for overrange capability in current mode, the user can also select the internal current sense resistor to be 14.7 kΩ, giving a nominal 2% overrange capability. This feature is available in the 0 mA to 20 mA, 4 mA to 20 mA, and ±20 mA current ranges. The stability of the output current value over temperature is dependent on the stability of the value of RSET. As a method of improving the stability of the output current over temperature, an external low drift resistor can be connected to the REXT1 and REXT2 pins of the AD5750/AD5750-1, which can be used instead of the internal resistor. The external resistor is selected via the input shift register. If the external resistor option is not used, the REXT1 and REXT2 pins should be left floating. PACKET ERROR CHECKING To verify that data has been received correctly in noisy environments, the AD5750/AD5750-1 offer the option of error checking based on an 8-bit (CRC-8) cyclic redundancy check. The device controlling the AD5750/AD5750-1 should generate an 8-bit frame check sequence using the following polynomial: C(x) = x8 + x2 + x1 + 1 This is added to the end of the data-word, and 24 data bits are sent to the AD5750/AD5750-1 before taking SYNC high. If the AD5750/AD5750-1 receive a 24-bit data frame, the parts perform the error check when SYNC goes high. If the check is valid, then the data is written to the selected register. If the error check fails, the FAULT pin goes low and Bit D3 of the status register is set. After reading this register, this error flag is cleared automatically and the FAULT pin goes high again. UPDATE ON SYNC HIGH SYNC PROGRAMMABLE OVERRANGE MODES The AD5750/AD5750-1 contain an overrange mode for most of the available ranges. The overranges are selected by configuring the R3, R1, R1, and R0 bits (or pins) accordingly. In voltage mode, the overranges are typically 20%, providing programmable output ranges of 0 V to 6 V, 0 V to 12 V, ±6 V, and ±12 V. The analog input remains the same. In current mode, the overranges are typically 2%. In current mode, the overrange capability is only available on three ranges, 0 mA to 20 mA, 0 mA to 24 mA, and 4 mA to 20 mA. For these ranges, the analog input also remains the same (0 V to 4.096 V for the AD5750, 0 V to 2.5 V for the AD5750-1). SCLK D15 (MSB) SDIN 16-BIT DATA 16-BIT DATA TRANSER—NO ERROR CHECKING D0 (LSB) SYNC UPDATE AFTER SYNC HIGH ONLY IF ERROR CHECK PASSED SCLK D23 (MSB) SDIN 16-BIT DATA D8 (LSB) D7 D0 8-BIT FCS 16-BIT DATA TRANSER WITH ERROR CHECKING Figure 55. PEC Error Checking Timing Rev. A | Page 30 of 36 07268-049 FAULT FAULT GOES LOW IF ERROR CHECK FAILS AD5750/AD5750-1 APPLICATIONS INFORMATION TRANSIENT VOLTAGE PROTECTION The AD5750/AD5750-1 contain ESD protection diodes that prevent damage from normal handling. The industrial control environment can, however, subject I/O circuits to much higher transients. To protect the AD5750/AD5750-1 from excessively high voltage transients, external power diodes and a surge current limiting resistor may be required, as shown in Figure 56. The constraint on the resistor value is that during normal operation the output level at IOUT must remain within its voltage compliance limit of AVDD − 2.75 V and the two protection diodes and resistor must have appropriate power ratings. Further protection can be added with transient voltage suppressors if needed. AVDD LAYOUT GUIDELINES In any circuit where accuracy is important, careful consideration of the power supply and ground return layout helps to ensure the rated performance. The PCB on which the AD5750/AD5750-1 are mounted should be designed so that the AD5750/AD5750-1 lie on the analog plane. The AD5750/AD5750-1 should have ample supply bypassing of 10 μF in parallel with 0.1 μF on each supply located as close to the package as possible, ideally right up against the device. The 10 μF capacitors are the tantalum bead type. The 0.1 μF capacitor should have low effective series resistance (ESR) and low effective series inductance (ESI) such as the common ceramic types, which provide a low impedance path to ground at high frequencies to handle transient currents due to internal logic switching. In systems where there are many devices on one board, it is often useful to provide some heat sinking capability to allow the power to dissipate easily. AVDD AD5750/AD5750-1 IOUT RP RLOAD 07268-050 AD5750/AD5750-1 AVSS Figure 56. Output Transient Voltage Protection THERMAL CONSIDERATIONS It is important to understand the effects of power dissipation on the package and how it affects junction temperature. The internal junction temperature should not exceed 125°C. The AD5750/ AD5750-1 are packaged in a 32-lead, 5 mm × 5 mm LFCSP package. The thermal impedance, θJA, is 28°C/W. It is important that the devices are not operated under conditions that cause the junction temperature to exceed its junction temperature. Worst-case conditions occur when the AD5750/AD5750-1 are operated from the maximum AVDD (26.4 V) and driving the maximum current (24 mA) directly to ground. The quiescent current of the AD5750/AD5750-1 should also be taken into account, nominally ~4 mA. The following calculations estimate maximum power dissipation under these worst-case conditions, and determine maximum ambient temperature based on this: Power Dissipation = 26.4 V × 28 mA = 0.7392 W Temp Increase = 28°C × 0.7392 W = 20.7°C Maximum Ambient Temp = 125°C − 20.7°C = 104.3°C These figures assume proper layout and grounding techniques are followed to minimize power dissipation, as outlined in the Layout Guidelines section. AVSS PLANE BOARD Figure 57. Paddle Connection to Board The AD5750/AD5750-1 have an exposed paddle beneath the device. Connect this paddle to the AVSS supply for the part. For optimum performance, special considerations should be used to design the motherboard and to mount the package. For enhanced thermal, electrical, and board level performance, the exposed paddle on the bottom of the package should be soldered to the corresponding thermal land paddle on the PCB. Thermal vias should be designed into the PCB land paddle area to further improve heat dissipation. The AVSS plane on the device can be increased (as shown in Figure 57) to provide a natural heat sinking effect. Rev. A | Page 31 of 36 07268-051 AD5750/AD5750-1 GALVANICALLY ISOLATED INTERFACE In many process control applications, it is necessary to provide an isolation barrier between the controller and the unit being controlled to protect and isolate the controlling circuitry from any hazardous common-mode voltages that may occur. The iCoupler® family of products from Analog Devices, Inc., provides voltage isolation in excess of 5.0 kV. The serial loading structure of the AD5750/AD5750-1 makes it ideal for isolated interfaces because the number of interface lines is kept to a minimum. Figure 58 shows a 4-channel isolated interface using an ADuM1400. For further information, visit www.analog.com/icouplers. CONTROLLER SERIAL CLOCK OUT SERIAL DATA OUT SYNC OUT MICROPROCESSOR INTERFACING Microprocessor interfacing to the AD5750/AD5750-1 is via a serial bus that uses a protocol compatible with microcontrollers and DSP processors. The communication channel is a 3-wire (minimum) interface consisting of a clock signal, a data signal, and a SYNC signal. The AD5750/AD5750-1 require a 16-bit data-word with data valid on the falling edge of SCLK. ADuM14001 DECODE ENCODE VIA VOA DECODE TO SCLK TO SDIN TO SYNC TO CLEAR 07268-052 ENCODE VIB ENCODE VOB DECODE VIC VOC DECODE ENCODE CONTROL OUT VID VOD 1ADDITIONAL PINS OMITTED FOR CLARITY. Figure 58. Isolated Interface Rev. A | Page 32 of 36 AD5750/AD5750-1 OUTLINE DIMENSIONS 5.00 BSC SQ 0.60 MAX 0.60 MAX 25 24 32 1 PIN 1 INDICATOR PIN 1 INDICATOR TOP VIEW 4.75 BSC SQ 0.50 BSC EXPOSED PAD (BOTTOM VIEW) 17 16 8 3.25 3.10 SQ 2.95 0.50 0.40 0.30 9 0.25 MIN 3.50 REF 12° MAX 0.80 MAX 0.65 TYP 0.05 MAX 0.02 NOM 1.00 0.85 0.80 COMPLIANT TO JEDEC STANDARDS MO-220-VHHD-2 Figure 59. 32-Lead Lead Frame Chip Scale Package [LFCSP_VQ] 5 mm × 5 mm Body, Very Thin Quad (CP-32-2) Dimensions shown in millimeters ORDERING GUIDE Model AD5750ACPZ-REEL 1 AD5750ACPZ-REEL71 AD5750BCPZ-REEL1 AD5750BCPZ-REEL71 AD5750-1ACPZ-REEL1 AD5750-1ACPZ-REEL71 AD5750-1BCPZ-REEL1 AD5750-1BCPZ-REEL71 1 TUE Accuracy ±0.3% ±0.3% ±0.1% ±0.1% ±0.3% ±0.3% ±0.1% ±0.1% Analog Input Range 0 V to 4.096 V 0 V to 4.096 V 0 V to 4.096 V 0 V to 4.096 V 0 V to 2.5 V 0 V to 2.5 V 0 V to 2.5 V 0 V to 2.5 V External Reference 4.096 V 4.096 V 4.096 V 4.096 V 1.25 V 1.25 V 1.25 V 1.25 V Temperature Range −40°C to +105°C −40°C to +105°C −40°C to +105°C −40°C to +105°C −40°C to +105°C −40°C to +105°C −40°C to +105°C −40°C to +105°C Package Description 32-Lead LFCSP_VQ 32-Lead LFCSP_VQ 32-Lead LFCSP_VQ 32-Lead LFCSP_VQ 32-Lead LFCSP_VQ 32-Lead LFCSP_VQ 32-Lead LFCSP_VQ 32-Lead LFCSP_VQ 011708-A SEATING PLANE 0.30 0.23 0.18 0.20 REF COPLANARITY 0.08 FOR PROPER CONNECTION OF THE EXPOSED PAD, REFER TO THE PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SECTION OF THIS DATA SHEET. Package Option CP-32-2 CP-32-2 CP-32-2 CP-32-2 CP-32-2 CP-32-2 CP-32-2 CP-32-2 Z = RoHS Compliant Part. Rev. A | Page 33 of 36 AD5750/AD5750-1 NOTES Rev. A | Page 34 of 36 AD5750/AD5750-1 NOTES Rev. A | Page 35 of 36 AD5750/AD5750-1 NOTES ©2009 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D07268-0-8/09(A) Rev. A | Page 36 of 36