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100101

FEATURES

§ Two linear taper potentiometers

- DS1855-010 (one 10k, 100 position and

one 10k, 256 position)

- DS1855-020 (one 10k, 100 position and

one 20k, 256 position)

- DS1855-050 (one 10k, 100 position and

one 50k, 256 position)

- DS1855-100 (one 10k, 100 position and

one 100k, 256 position)

§ 256 bytes of EEPROM memory

§ Access to data and potentiometer control via

a 2-wire interface

§ External write-protect pin to protect data and

potentiometer settings

§ Data and potentiometer settings also can be

write-protected through software control

§ Nonvolatile wiper storage

§ Operates from 3V or 5V supplies

§ Packaging: 14-pin TSSOP, 16-ball STPBGA,

flip-chip package

§ Industrial operating temperature:

-40ºC to +85ºC

§ Programming temperature: 0ºC to +85ºC

DESCRIPTION

The DS1855 dual nonvolatile (NV) digital potentiometer and secure memory consists of one 100-position

linear taper potentiometer, one 256-position linear taper potentiometer, 256 bytes of EEPROM memory,

and a 2-wire interface. The DS1855, which features a new software write protect, is an upgrade of the

DS1845. The DS1855 provides an ideal method for setting bias voltages and currents in control

applications using a minimum of circuitry. The EEPROM memory allows a user to store configuration or

calibration data for a specific system or device as well as provide control of the potentiometer wiper

settings. Any type of user information may reside in the first 248 bytes of this memory. The next two

addresses of EEPROM memory are for potentiometer settings and the remaining 6 bytes of memory are

reserved. These reserved and potentiometer registers should not be used for data storage. Access to this

EEPROM is via an industry-standard 2-wire bus. The interface I/O pins consist of SDA and SCL. The

wiper position of the DS1855, as well as EEPROM data, can be write-protected through hardware using

the

write-protect

input

pin

(WP)

or

software

using

the

2-wire

interface.

DS1855

Dual Nonvolatile Digital Potentiometer

and Secure Memory

www.maxim-ic.com

SDA

1

14

Vcc

SCL

2

13

H0

A0

3

12

W1

A1

4

11

H1

A2

5

10

L1

WP

6

9

W0

GND

78

L0

14-Pin TSSOP (173-mil)

A

B

C

D

1

2

3

4

Top View

16-Ball STPBGA (4mm x 4mm)

14-Pin Flip Chip (100-mil x 100-mil)

(Not Shown)