1

®

FN8174.1

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.

X9271

Single Supply/Low Power/256-Tap/SPI Bus

Single Digitally-Controlled (XDCP™)

Potentiometer

FEATURES

• 256 Resistor Taps

• SPI Serial Interface for write, read, and transfer

operations of the potentiometer

• Wiper Resistance, 100

• 16 Nonvolatile Data Registers

• Nonvolatile Storage of Multiple Wiper Positions

• Power-on Recall. Loads Saved Wiper Position on

Power-up.

• Standby Current < 3µA Max

•50k

Ω, 100kΩ versions of End to End Resistance

• 100 yr. Data Retention

• Endurance: 100,000 Data Changes per Bit per

Register

• 14-Lead TSSOP

• Low Power CMOS

DESCRIPTION

The X9271 integrates a single digitally controlled

potentiometer

(XDCP)

on

a

monolithic

CMOS

integrated circuit.

The digital 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. The potentiometer has associated with it a

volatile Wiper Counter Register (WCR) and a four

nonvolatile 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. Powerup 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.

FUNCTIONAL DIAGRAM

50k

Ω and 100kΩ

POT

SPI

Bus

Power-on Recall

Wiper Counter

Register (WCR)

Data Registers

16 Bytes

Interface

Bus

Interface

and Control

Address

Data

Status

Write

Read

Transfer

Inc/Dec

Control

256-taps

Data Sheet

March 31, 2005