CAT5269

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3

PIN DESCRIPTIONS

Table 1. PIN DESCRIPTIONS

Pin #

Name

Function

1

NC

No Connect

2

A0

Device Address, LSB

3

NC

No Connect

4

NC

No Connect

5

NC

No Connect

6

NC

No Connect

7

Supply Voltage

8

Low Reference Terminal for

Potentiometer 0

9

High Reference Terminal for

Potentiometer 0

10

Wiper Terminal for Potentiometer 0

11

A2

Device Address

12

WP

Write Protection

13

SDA

Serial Data Input/Output

14

A1

Device Address

15

Low Reference Terminal for

Potentiometer 1

16

High Reference Terminal for

Potentiometer 1

17

Wiper Terminal for Potentiometer 1

18

GND

Ground

19

NC

No Connect

20

NC

No Connect

21

NC

No Connect

22

NC

No Connect

23

SCL

Bus Serial Clock

24

A3

Device Address

SCL: Serial Clock

The CAT5269 serial clock input pin is used to clock all data

transfers into or out of the device.

SDA: Serial Data

The CAT5269 bidirectional serial data pin is used to transfer

data into and out of the device. The SDA pin is an open drain

output and can be wire-Ored with the other open drain or

open collector I/Os.

A0, A1, A2, A3: Device Address Inputs

These inputs set the device address when addressing

multiple devices. A total of sixteen devices can be addressed

on a single bus. A match in the slave address must be made

with the address input in order to initiate communication

with the CAT5269.

connections on a mechanical potentiometer.

mechanical potentiometer.

WP: Write Protect Input

The WP pin when tied low prevents non-volatile writes to

the data register (change of wiper control register is allowed)

and when tied high or left floating normal read/write

operations are allowed. See Write Protection on page 8 for

more details.

DEVICE OPERATION

The CAT5269 is two resistor arrays integrated with a

2-wire serial interface, two 8-bit wiper control registers and

eight 8-bit, non-volatile memory data registers. Each

resistor array contains 255 separate resistive elements

connected in series. The physical ends of each array are

equivalent to the fixed terminals of a mechanical

at the ends of the series resistors are connected to the output

one tap point for each potentiometer is connected to its wiper

terminal at a time and is determined by the value of the wiper

control register. Data can be read or written to the wiper

control registers or the non-volatile memory data registers

via the 2-wire bus. Additional instructions allow data to be

transferred between the wiper control registers and each

respective potentiometer’s non-volatile data registers. Also,

the device can be instructed to operate in an “increment/

decrement” mode.