DS1846

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The EEPROM memory allows a user to store configuration or calibration data for a specific system or

device and provides control of the potentiometer wiper settings. Any type of user information can reside

in the first 248 bytes (00h to F7h) of this memory. The next three bytes of memory (F8h to FAh) are for

potentiometer settings and the last five addresses of EEPROM memory (FBh to FFh) are reserved. These

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

through an industry-standard 2-wire bus. The interface I/O pins consist of SDA and SCL. The wiper

positions of the DS1846, as well as EEPROM data, can be hardware write-protected using the WP input

pin.

The MicroMonitor is a precision temperature-compensated reference and comparator that monitors

condition, a nonmaskable interrupt is generated. As the voltage at the device degrades, an internal power-

power supply and the microprocessor. The MicroMonitor also functions as a pushbutton reset control.

DS1846 BLOCK DIAGRAM Figure 1

DS1846

2-Wire

Interface

SCL

SDA

WP

A0

5 Reserved

Bytes

FBh-FFh

Potentiometer 2

FAh

Potentiometer 0

F9h

Potentiometer 1

F8h

User EPROM

248 Bytes

00h-F7h

EEPROM

Potentiometer 2

H2

W2

L2

10k

W

Addr FAh

100-Positions

Potentiometer 0

H0

W0

L0

10k

W

Addr F9h

100-Positions

Potentiometer 1

H1

W1

L1

100k

W

Addr F8h

256-Positions

Data

Nonvolatile

Digital Potentiometer

PBRST

V

CCTP

V

TP

V

CC

IN

RST

RST

V

CC

NMI

MicroMonitor

Timer

Delay

Timer

Delay

V

CC

2.4k

W

typical