1

®

X9250

Low Noise/Low Power/SPI Bus/256 Taps

Quad Digitally Controlled Potentiometers

(XDCP™)

FEATURES

• Four potentiometers in one package

• 256 resistor taps/pot - 0.4% resolution

• SPI serial interface

• Wiper resistance, 40

• Four nonvolatile data registers for each pot

• Nonvolatile storage of wiper position

• Standby current < 5µA max (total package)

• Power supplies

—V+ = 2.7V to 5.5V

—V– = -2.7V to -5.5V

• 100k

Ω, 50kΩ total pot resistance

• High reliability

—Endurance – 100,000 data changes per bit per

register

—Register data retention - 100 years

• 24-lead SOIC, 24-lead TSSOP

• Dual supply version of X9251

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.

BLOCK DIAGRAM

Wiper

Counter

Register

(WCR)

Resistor

Array

Wiper

Counter

Register

(WCR)

Interface

and

Control

Circuitry

CS

SCK

A0

A1

Data

8

SO

SI

Wiper

Counter

Register

(WCR)

Resistor

Array

Pot 2

Wiper

Counter

Register

(WCR)

Resistor

Array

Pot 3

Pot1

HOLD

WP

Pot 0

V+

V-

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

FN8165.1

March 25, 2005