GENERAL DESCRIPTION

The AD5232 device provides a nonvolatile, dual-channel, digitally controlled variable resistor (VR) with 256-position resolution. This device performs the same electronic adjustment function as a mechanical potentiometer with enhanced resolution, solid state reliability, and superior low temperature coefficient performance. The versatile programming of the AD5232, per ormed via a microcontroller, allows multiple modes of operation and adjustment.

In the direct program mode, a predetermined setting of the RDAC registers (RDAC1 and RDAC2) can be loaded directly from the microcontroller. Another important mode of operation allows the RDACx register to be refreshed with the setting previously stored in the corresponding EEMEM register (EEMEM1 and EEMEM2). When changes are made to the RDACx register to establish a new wiper position, the value of the setting can be saved into the EEMEMx register by executing an EEMEM save operation. After the settings are saved in the EEMEMx register, these values are automatically transferred to the RDACx register to set the wiper position at system power-on. Such operation is enabled by the internal preset strobe. The preset strobe can also be accessed externally.

FEATURES

Dual-channel, 256-position resolution

10 kΩ, 50 kΩ, and 100 kΩ nominal terminal resistance

Nonvolatile memory maintenance of wiper settings

Predefined linear increment/decrement instructions

Predefined ±6 dB step log taper increment/decrement

instructions

SPI-compatible serial interface

Wiper settings and EEMEM readback

3 V to 5 V single-supply operation

±2.5 V dual-supply operation

14 bytes of general-purpose user EEMEM

Permanent memory write protection

100-year typical data retention (TA = 55°C)

APPLICATIONS

Mechanical potentiometer replacement

Instrumentation: gain and offset adjustment

Programmable voltage-to-current conversion

Programmable filters, delays, and time constants

Programmable power supply

Low resolution DAC replacement

Sensor calibration