DESCRIPTION

The X9250 integrates 4 digitally controlled

potentiometers (XDCP) on a monolithic CMOS

integrated circuit.

The digitally controlled potentiometer is implemented

using 255 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. Each potentiometer has associated

with it a volatile Wiper Counter Register (WCR) and 4

nonvolatile Data Registers (DR0:DR3) 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 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.

FEATURES

? Four potentiometers in one package

? 256 resistor taps/pot - 0.4 resolution

? SPI serial interface

? Wiper resistance, 40? typical @ VCC = 5V

? Four nonvolatile data registers for each pot

? Nonvolatile storage of wiper position

? Standby current < 5μA max (total package)

? Power supplies

—VCC = 2.7V to 5.5V

—V+ = 2.7V to 5.5V

—V– = -2.7V to -5.5V

? 100k?, 50k? total pot resistance

? High reliability

—Endurance – 100,000 data changes per bit per

register

—Register data retention - 100 years

? 24 Ld SOIC, 24 Ld TSSOP

? Dual supply version of X9251

? Pb-free plus anneal available (RoHS compliant)