AD5231 Analog Devices Data Sheet

Nonvolatile Memory,

1024-Position Digital Potentiometer

AD5231 FEATURES FUNCTIONAL BLOCK DIAGRAM 1024-position resolution AD5231

CS VDD

Nonvolatile memory maintains wiper setting

ADDR RDAC RDACCLK DECODE REGISTER

Power-on refresh with EEMEM setting

SDI SDI

EEMEM restore time: 140 μs typ

SERIAL

Full monotonic operation GND

INTERFACE EEMEM(0)

10 kΩ, 50 kΩ, and 100 kΩ terminal resistance Permanent memory write protection SDO SDO

DIGITAL

Wiper setting readback REGISTER

WP DIGITAL

EEMEM O2

OUTOUT

Predefined linear increment/decrement instructions CONTROL

RDY BUFFER

Predefined ±6 d B/step log taper increment/decrement EEMEM(1)

instructions 28 BYTES VSS

USER EEMEM

SPI®-compatible serial interface

3 V to 5 V single-supply or ±2.5 V dual-supply operation

Figure 1.

28 bytes extra nonvolatile memory for user-defined data 100-year typical data retention, TA = 55°C

RWBRWA

APPLICATIONS (D (D f N om in al

Mechanical potentiometer replacement Instrumentation: gain, offset adjustment Programmable voltage to current conversion Programmable filters, delays, time constants

Programmable power supply w.BDTIC.com/ADI Low resolution DAC replacement Sensor calibration

CODE (Decimal)

Figure 2. RWA (D) and RWB (D) vs. Decimal Code

GENERAL DESCRIPTION

The AD5231 is a nonvolatile memory1, digitally controlled resistance between Terminals W–A and Terminals W–B. This potentiometer2 with 1024-step resolution. The device performs setting can be stored into the EEMEM and is transferred the same electronic adjustment function as a mechanical automatically to the RDAC register during system power-on. potentiometer with enhanced resolution, solid state reliability, 9- The EEMEM content can be restored dynamically or through

and remote controllability. The AD5231 has versatile programming

external PR strobing, and a WP function protects EEMEM

that uses a standard 3-wire serial interface for 16 modes of

contents. To simplify the programming, the linear-step increment

operation and adjustment, including scratchpad programming,

or decrement commands can be used to move the RDAC wiper

memory storing and restoring, increment/decrement, ±6 d B/step

up or down, one step at a time. The ±6 d B step commands can

log taper adjustment, wiper setting readback, and extra EEMEM

be used to double or half the RDAC wiper setting.

for user-defined information, such as memory data for other

The AD5231 is available in a 16-lead TSSOP. The part is

components, look-up table, or system identification information.

guaranteed to operate over the extended industrial temperature

In scratchpad programming mode, a specific setting can be

range of −40°C to +85°C.

programmed directly to the RDAC register that sets the

1 The terms nonvolatile memory and EEMEM are used interchangeably.

2 The terms digital potentiometer and RDAC are used interchangeably.

Rev. C 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

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