GENERAL DESCRIPTION

The AD5251/AD5252 are dual-channel, I2C®, nonvolatile memory, digitally controlled potentiometers with 64/256 positions, respectively. These devices perform the same electronic adjustment functions as mechanical potentiometers, trimmers, and variable resistors. The parts’ versatile programmability allows multiple modes of operation, including read/write access in the RDAC and EEMEM registers, increment/decrement of resistance, resistance changes in ±6 dB scales, wiper setting readback, and extra EEMEM for storing user-defined information, such as memory data for other components, look-up table, or system identification information.

FEATURES

AD5251: Dual 64-position resolution

AD5252: Dual 256-position resolution

1 kΩ, 10 kΩ, 50 kΩ, 100 kΩ

Nonvolatile memory1 stores wiper setting w/write protection

Power-on refreshed with EEMEM settings in 300 µs typ

EEMEM rewrite time = 540 µs typ

Resistance tolerance stored in nonvolatile memory

12 extra bytes in EEMEM for user-defined information

I2C-compatible serial interface

Direct read/write access of RDAC2 and EEMEM registers

Predefined linear increment/decrement commands

Predefined ±6 dB step change commands

Synchronous or asynchronous dual-channel update

Wiper setting readback

4 MHz bandwidth—1 kΩ version

Single supply 2.7 V to 5.5 V

Dual supply ±2.25 V to ±2.75 V

2 slave address decoding bits allow operation of 4 devices

100-year typical data retention, TA = 55°C

Operating temperature: –40°C to +105°C

APPLICATIONS

Mechanical potentiometer replacement

General-purpose DAC replacement

LCD panel VCOM adjustment

White LED brightness adjustment

RF base station power amp bias control

Programmable gain and offset control

Programmable voltage-to-current conversion

Programmable power supply

Sensor calibrations