FN8196 Rev.1.00

Page 1 of 20

January 14, 2009

FN8196

Rev.1.00

January 14, 2009

X9421

Low Noise/Low Power/SPI Bus Single Digitally Controlled (XDCP™)

Potentiometer

DATASHEET

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 1-888-468-3774

XDCP is a trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2005, 2008, 2009. All Rights Reserved

All other trademarks mentioned are the property of their respective owners.

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.

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.

• Standby Current < 5µA Max

•2.5k

, 10k End to End Resistance

• 100 yr. Data Retention

• Endurance: 100, 000 Data Changes per Bit per Register

• 14 Ld TSSOP, 16 Ld SOIC

• Low Power CMOS

• Pb-Free Available (RoHS Compliant)

Block Diagram

64-TAPS

10k



INC / DEC

POT

SPI

BUS

ADDRESS

DATA

STATUS

WRITE

READ

WIPER

TRANSFER

POWER-ON RECALL

WIPER COUNTER

REGISTER (WCR)

DATA REGISTERS

4 BYTES

CONTROL

INTERFACE

BUS

INTERFACE &

CONTROL

NOT RECOMMENDED FOR NEW DESIGNS

POSSIBLE SUBSTITUTE PRODUCT

ISL22416, ISL22419