The AD5232 device provides a nonvolatile, dual-channel, digitally controlled variable resistor (VR) with 256-bit resolution. These devices perform the same electronic adjustment function as a potentiometer or variable resistor. "The AD5232 allows multiple modes of operation and adjustment through general-purpose programming of a microcontroller. In the direct programming mode the pre-set RDAC registers from the microcontroller can be loaded directly. Another key operating mode allows the RDAC registers to be combined with The settings previously stored in the EEMEM are refreshed. When the RDAC register is changed to establish a new wiper position, the set value can be saved to the EEMEM to perform an EEMEM save operation. Once the settings are saved in the EEMEM register these values will be automatically transferred to the RDAC register set Wiper position on system power-up. This operation is enabled by the internal preset flash and the preset can also be accessed externally. The contents of all internal registers can be read out of the serial data output (SDO). This includes the RDAC1 and RDAC2 registers, the corresponding non- Volatile EEMEM1 and EEMEM2 registers, 14 alternate user EEMEM registers for constant storage. The basic mode of adjustment is the increment and decrement commands control the wiper position setting (RDAC) register. The RDAC register of the internal note can be moved up or down in nominal A step of termination is the resistance between terminals A and B that varies linearly by one position segment of the wiper to B's terminating resistor (RWB) of the device's "terminal-to-terminal resistor (RAB). For exponential/logarithmic tap settings, the left/right shift command changes the level in ±6 dB steps to adjust the level, useful for audio alarm applications. The AD5232 is available in the thin TSSOP-16 package. All parts are guaranteed to operate over the extended industrial temperature range of -40°C to +85°C. Evaluation board, model: AD5232EVAL.