The X9271 integrates a digitally controlled potentiometer (XDCP™) on a monolithic CMOS integrated circuit. The digital control potentiometer is realized by a series array of 255 resistance elements. Between each element are contacts connected to the wiper terminal by a switch.
Function diagram
The location of the wiper on the array is controlled by the user through the SPI bus interface. The potentiometer is associated with a volatile wiper counter register (WCR) and four non-volatile data registers that can be written and read directly by the user. The contents of the WCR control the wiper position on the resistance array via a switch.
Power-up recalls the contents of the default data register (DR0) to WCR. XDCP can be used as a three-terminal potentiometer or a two-end variable resistor for a variety of applications including control, parameter adjustment, and signal processing.
Detailed function diagram
