ISL22424 pdf datasheet (Low No

The ISL22424 integrates two digitally controlled
potentiometers (DCP), control logic and non-volatile memory
on a monolithic CMOS integrated circuit.
The digitally controlled potentiometers are implemented with
a combination of resistor elements and CMOS switches. The
position of the wiper is controlled by the user through the SPI
serial interface. Each potentiometer has an associated
volatile Wiper Register (WRi) and a non-volatile Initial Value
Register (IVRi) that can be directly written to and read by the
user. The contents of the WRi control the position of the
wiper. At power-up the device recalls the contents of the
DCP’s IVRi to the corresponding WRi.
The ISL22424 also has 13 General Purpose non-volatile
registers that can be used as storage of lookup table for
multiple wiper position or any other valuable information.
The ISL22424 features a dual supply, that is beneficial for
applications requiring a bipolar range for DCP terminals
between V- and VCC.