Nonvolatile Memory, 1024-Position Digital …

1 Nonvolatile memory , 1024-Position Digital potentiometer data sheet AD5231 Rev. D Document Feedback 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, Box 9106, Norwood, MA 02062-9106, Tel: 2001 2013 analog devices , Inc.

2 All rights reserved. Technical Support FEATURES 1024-Position resolution Nonvolatile memory maintains wiper setting Power-on refresh with EEMEM setting EEMEM restore time: 140 s typ Full monotonic operation 10 k , 50 k , and 100 k terminal resistance Permanent memory write protection Wiper setting readback Predefined linear increment/decrement instructions Predefined 6 dB/step log taper increment/decrement instructions SPI -compatible serial interface 3 V to 5 V single-supply or V dual-supply operation 28 bytes extra Nonvolatile memory for user-defined data 100-year typical data retention, TA = 55 C APPLICATIONS Mechanical potentiometer replacement Instrumentation.

3 Gain, offset adjustment Programmable voltage to current conversion Programmable filters, delays, time constants Programmable power supply Low resolution DAC replacement Sensor calibration FUNCTIONAL BLOCK DIAGRAM EEMEM(0)EEMEM(1)AD5231 RDACCLKSDIGNDSDORDYSDOVDDVSSAWBO1O2 SDI2 PRWPCSADDRDECODERDACREGISTERDIGITALREGIS TERSERIALINTERFACEEEMEMCONTROL28 BYTESUSER EEMEMDIGITALOUTOUTBUFFER02739-001 Figure 1. CODE (Decimal)10075001023256 RWA(D), RWB(D); (% of Nominal RAB)5127685025 RWBRWA02739-002 Figure 2. RWA (D) and RWB (D) vs. Decimal CodeGENERAL DESCRIPTIONThe AD5231 is a Nonvolatile memory1, digitally controlled potentiometer2 with 1024-step resolution. The device performs the same electronic adjustment function as a mechanical potentiometer with enhanced resolution, solid state reliability, and remote controllability.

4 The AD5231 has versatile programming that uses a standard 3-wire serial interface for 16 modes of operation and adjustment, including scratchpad programming, memory storing and restoring, increment/decrement, 6 dB/step log taper adjustment, wiper setting readback, and extra EEMEM for user-defined information, such as memory data for other components, look-up table, or system identification information. In scratchpad programming mode, a specific setting can be programmed directly to the RDAC register that sets the resistance between Terminals W A and Terminals W B. This setting can be stored into the EEMEM and is transferred automatically to the RDAC register during system power-on.

5 The EEMEM content can be restored dynamically or through external PR strobing, and a WP function protects EEMEM contents. To simplify the programming, the linear-step increment or decrement commands can be used to move the RDAC wiper up or down, one step at a time. The 6 dB step commands can be used to double or half the RDAC wiper setting. The AD5231 is available in a 16-lead TSSOP. The part is guaranteed to operate over the extended industrial temperature range of 40 C to +85 C. 1 The terms Nonvolatile memory and EEMEM are used interchangeably. 2 The terms Digital potentiometer and RDAC are used interchangeably. AD5231 data sheet Rev. D | Page 2 of 28 TABLE OF CONTENTS Features.

6 1 Applications .. 1 Functional Block Diagram .. 1 General Description .. 1 Revision History .. 2 Specifications .. 3 Electrical Characteristics 10 k , 50 k , 100 k Versions .. 3 Timing Characteristics 10 k , 50 k , 100 k Versions .. 5 Absolute Maximum Ratings .. 7 ESD Caution .. 7 Pin Configuration and Function Descriptions .. 8 Typical Performance Characteristics .. 9 Test Circuits .. 13 Theory of Operation .. 14 Scratchpad and EEMEM Programming .. 14 Basic Operation .. 14 EEMEM Protection .. 14 Digital Input/Output Configuration .. 15 Serial data Interface .. 15 Daisy-Chain Operation .. 15 Terminal Voltage Operation Range .. 16 Power-Up Sequence .. 16 Latched Digital Outputs.

7 16 Advanced Control Modes .. 18 RDAC 19 Programming the Variable Resistor .. 19 Programming the potentiometer Divider .. 20 Programming Examples .. 21 Flash/EEMEM Reliability .. 22 Applications .. 23 Bipolar Operation from Dual 23 High Voltage Operation .. 23 Bipolar Programmable Gain Amplifier .. 23 10-Bit Bipolar DAC .. 23 10-Bit Unipolar DAC .. 24 Programmable Voltage Source with Boosted Output .. 24 Programmable Current Source .. 24 Programmable Bidirectional Current Source .. 25 Resistance Scaling .. 25 RDAC Circuit Simulation Model .. 26 Outline Dimensions .. 27 Ordering Guide .. 27 REVISION HISTORY3/13 Rev. C to Rev. D Added tWP; Table 2 .. 5 Changes to Ordering Guide.

8 27 1/07 Rev. B to Rev. C Updated Format .. Universal Changes to Dynamic Characteristics Specifications .. 4 Changes to Table 2 Footnote .. 5 Changes to Ta b l e 3 .. 7 Changes to Ordering Guide .. 27 9/04 Rev. A to Rev. B Updated Format .. Universal Changes to Table 20 .. 23 Changes to Resistance Scaling Section .. 25 Changes to Ordering Guide .. 27 5/04 Rev. 0 to Rev. A Updated formatting .. Universal Edits to Features, General Description, and Block Diagram .. 1 Changes to Specifications .. 3 Replaced Timing 6 Changes to Pin Function Descriptions .. 8 Changes to Typical Performance 9 Changes to Test Circuits .. 13 Edits to Theory of Operation .. 14 Edits to Applications.

9 23 Updated Outline Dimensions .. 27 12/01 Revision 0: Initial Version data sheet AD5231 Rev. D | Page 3 of 28 SPECIFICATIONS ELECTRICAL CHARACTERISTICS 10 k , 50 k , 100 k VERSIONS VDD = 3 V 10% or 5 V 10%, VSS = 0 V, VA = VDD, VB = 0 V, 40 C < TA < +85 C, unless otherwise noted. Table 1. Parameter Symbol Conditions Min Typ1 Max Unit DC CHARACTERISTICS RHEOSTAT MODE Resistor Differential Nonlinearity2 R-DNL RWB, VA = NC, monotonic 1 1/2 + LSB Resistor Integral Nonlinearity2 R-INL RWB,VA = NC + LSB Nominal Resistor Tolerance RAB/RAB D = 0x3FF 40 +20 % Resistance Temperature Coefficient ( RWB/RWB)/ T 106 600 ppm/ C Wiper Resistance RW IW = 100 A, VDD = V, code = half scale 15 100 IW = 100 A, VDD = 3 V, code = half scale 50 DC CHARACTERISTICS potentiometer DIVIDER MODE Resolution N 10 Bits Differential Nonlinearity3 DNL Monotonic, TA = 25 C 1 1/2 +1 LSB Monotonic, TA = 40 C or +85 C 1 + LSB Integral Nonlinearity3 INL + LSB Voltage Divider Temperature Coefficient ( VW/VW)

10 / T 106 Code = half scale 15 ppm/ C Full-Scale Error VWFSE Code = full scale 3 0 % FS Zero-Scale Error VWZSE Code = zero scale 0 % FS RESISTOR TERMINALS Terminal Voltage Range4 VA, B, W VSS VDD V Capacitance A, B5 CA, B f = 1 MHz, measured to GND, code = half-scale 50 pF Capacitance W5 CW f = 1 MHz, measured to GND, code = half-scale 50 pF Common-Mode Leakage Current5, 6 ICM VW = VDD/2 1 A Digital INPUTS AND OUTPUTS Input Logic High VIH With respect to GND, VDD = 5 V V Input Logic Low VIL With respect to GND, VDD = 5 V V Input Logic High VIH With respect to GND, VDD = 3 V V Input Logic Low VIL With respect to GND, VDD = 3 V V Input Logic High VIH With respect to GND, VDD = +2.