FN8172 Rev.4.00

Page 1 of 22

August 29, 2006

FN8172

Rev.4.00

August 29, 2006

X9268

Dual Supply/Low Power/256-Tap/2-Wire Bus Dual Digitally-Controlled (XDCP™)

Potentiometers

DATASHEET

FEATURES

• Dual–Two Separate Potentiometers

• 256 Resistor Taps/Pot–0.4% Resolution

• 2-Wire Serial Interface for Write, Read, and

Transfer Operations of the Potentiometer

• Wiper Resistance, 100

 typical @ V+ = 5V,

V- = -5V

• 16 Nonvolatile Data Registers for Each

Potentiometer

• Nonvolatile Storage of Multiple Wiper Positions

• Power-on Recall. Loads Saved Wiper Position on

Power-up.

• Standby Current <5µA Max

•50k

, 100k Versions of End to End Pot

Resistance

• Endurance: 100,000 Data Changes per Bit per

Register

• 100 yr. Data Retention

• 24 Ld SOIC

• Low Power CMOS

V+ = 2.7V to 5.5V

V- = -2.7V to -5.5V

• Pb-Free Plus Anneal Available (RoHS Compliant)

DESCRIPTION

The

X9268

integrates

2

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

2-Wire bus interface. Each 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

2-Wire

Bus

50k

 or 100k versions

Power-on Recall

Wiper Counter

Registers (WCR)

Data Registers

(DR0–DR3)

Interface

Bus

Interface

and Control

Address

Data

Status

Write

Read

Transfer

Inc/Dec

Control

V-