X9111

The X9111 integrates a single, digitally controlled potentiometer (XDCP) on a monolithic CMOS integrated circuit. The digital controlled potentiometer is implemented using 1023 resistive elements in a series array. Between each element are tap points connected to the wiper terminal through switches. The position of the wiper on the array is controlled by the user through the SPI bus interface. The potentiometer has associated with it a volatile Wiper Counter Register (WCR) and four nonvolatile Data Registers that can be directly written to and read by the user. The contents of the WCR control the position of the wiper on the resistor array through the switches. Power-up recalls the contents of the default data register (DR0) to the WCR. The XDCP can be used as a 3-terminal potentiometer or as a 2-terminal variable resistor in a wide variety of applications including control, parameter adjustments, and signal processing.