X9421

X9421 NOT RECOMMENDED FOR NEW DESIGNS POSSIBLE SUBSTITUTE PRODUCT ISL22416, ISL22419 Low Noise/Low Power/SPI Bus Single Digitally Controlled (XDCP™) Potentiometer DATASHEET FN8196 Rev.1.00 January 14, 2009 Description The X9421 integrates a single digitally controlled potentiometer (XDCP) on a monolithic CMOS integrated circuit. The digital controlled potentiometer is implemented using 63 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 a four non-volatile Data Registers that can be directly written to and read by the user. The contents of the WCR controls the position of the wiper on the resistor array though the switches. Power-up recalls the contents of the default data register (DR0) to the WCR. The XDCP can be used as a three-terminal potentiometer or as a two terminal variable resistor in a wide variety of applications including control, parameter adjustments, and signal processing. Block Diagram Features Single Voltage Potentiometer 64 Resistor Taps SPI Serial Interface for Write, Read, and Transfer Operations of the Potentiometer Wiper Resistance, 150 Typical at 5V 4 Non-Volatile Data Registers Non-Volatile Storage of Multiple Wiper Positions Power-on Recall. Loads Saved Wiper Position on Power-up...