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X9408

Low Noise/Low Power/2-Wire Bus

Quad Digitally Controlled (XDCP™)

Potentiometers

Description

The X9408 integrates four digitally controlled potentiometers

(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 2-wire bus interface. Each

potentiometer has associated with it a volatile Wiper Counter

Register (WCR) and 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

• Four Potentiometers in One Package

• 64 Resistor Taps per Potentiometer

• 2-wire Serial Interface

• Wiper Resistance, 40

Ω Typical at 5V

• Four Nonvolatile Data Registers for Each Pot

• Nonvolatile Storage of Wiper Position

• Standby Current < 1µA max (Total Package)

V+ = 2.7V to 5.5V

V- = -2.7V to -5.5V

•10k

Ω, 2.5kΩ End to End Resistances

• High reliability

• Endurance–100,000 Data Changes Per Bit Per Register

• Register Data Retention–100 years

• 24 Ld SOIC, 24 Ld TSSOP, 24 Ld PDIP Packages

• Pb-Free (RoHS Compliant)

Block Diagram

INTERFACE

AND

CONTROL

CIRCUITRY

SCL

SDA

A0

A1

A2

A3

R0

R1

R2

R3

WIPER

COUNTER

REGISTER

(WCR)

RESISTOR

ARRAY

POT 1

R0

R1

R2

R3

WIPER

COUNTER

REGISTER

(WCR)

DATA

8

R0

R1

R2

R3

RESISTOR

ARRAY

R0

R1

R2

R3

RESISTOR

ARRAY

WIPER

COUNTER

REGISTER

(WCR)

WIPER

COUNTER

REGISTER

(WCR)

POT 3

POT 2

WP

POT 0

V+

V-

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, 2009. All Rights Reserved

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

Data Sheet

FN8191.4

January 15, 2009