1

®

X9420

Low Noise/Low Power/SPI Bus

Single Digitally Controlled (XDCP™)

Potentiometer

FEATURES

• Solid-State Potentiometer

• SPI serial interface

• Register oriented format

—Direct read/write/transfer wiper positions

—Store as many as four positions per

potentiometer

• Power supplies

—V+ = 2.7V to 5.5V

—V– = -2.7V to -5.5V

• Low power CMOS

—Standby current < 1µA

• High reliability

—Endurance–100,000 data changes per bit per

register

—Register data retention–100 years

• 8-bytes of nonvolatile EEPROM memory

•10k

Ω or 2.5kΩ resistor arrays

• Resolution: 64 taps each pot

• 14-lead TSSOP, 16-lead SOIC, and 16-pin plastic

DIP packages

DESCRIPTION

The X9420 integrates a single digitally controlled

potentiometers

(XDCP)

on

a

monolithic

CMOS

integrated microcircuit.

The digitally 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

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 through 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.

BLOCK DIAGRAM

R0 R1

R2 R3

Wiper

Counter

Register

(WCR)

Interface

and

Control

Circuitry

HOLD

CS

SI

A0

Data

8

SCK

S0

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

1-888-INTERSIL or 1-888-352-6832

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

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

Data Sheet

FN8195.0

March 7, 2005