1

®

FN3093.3

ICL7135

The Intersil ICL7135 precision A/D converter, with its

multiplexed BCD output and digit drivers, combines dual-

slope conversion reliability with

±1 in 20,000 count accuracy

and is ideally suited for the visual display DVM/DPM market.

The 2.0000V full scale capability, auto-zero, and auto-

polarity are combined with true ratiometric operation, almost

ideal differential linearity and true differential input. All

necessary active devices are contained on a single CMOS

lC, with the exception of display drivers, reference, and a

clock.

The ICL7135 brings together an unprecedented combination

of high accuracy, versatility, and true economy. It features

auto-zero to less than 10

input bias current of 10pA (Max), and rollover error of less

than one count. The versatility of multiplexed BCD outputs is

increased by the addition of several pins which allow it to

operate in more sophisticated systems. These include

STROBE, OVERRANGE, UNDERRANGE, RUN/HOLD and

BUSY lines, making it possible to interface the circuit to a

microprocessor or UART.

Features

• Accuracy Guaranteed to

±1 Count Over Entire ±20000

Counts (2.0000V Full Scale)

• Guaranteed Zero Reading for 0V Input

• 1pA Typical Input Leakage Current

• True Differential Input

• True Polarity at Zero Count for Precise Null Detection

• Single Reference Voltage Required

• Overrange and Underrange Signals Available for Auto-

Range Capability

• All Outputs TTL Compatible

• Blinking Outputs Gives Visual Indication of Overrange

• Six Auxiliary Inputs/Outputs are Available for Interfacing to

UARTs, Microprocessors, or Other Circuitry

• Multiplexed BCD Outputs

•

Pb-Free Available (RoHS Compliant)

Pinout

ICL7135

(PDIP)

TOP VIEW

Ordering Information

PART NUMBER

TEMP.

RANGE (°C)

PACKAGE

PKG.

DWG. #

ICL7135CPI

0 to 70

28 Ld PDIP

E28.6

ICL7135CPIZ

(Note 1)

0 to 70

28 Ld PDIP

(Pb-free) (Note 2)

E28.6

NOTES:

1. Intersil Pb-free products employ special Pb-free material sets;

molding compounds/die attach materials and 100% matte tin

plate termination finish, which are RoHS compliant and

compatible with both SnPb and Pb-free soldering operations.

Intersil Pb-free products are MSL classified at Pb-free peak

reflow temperatures that meet or exceed the Pb-free

requirements of IPC/JEDEC J STD-020C.

2. Pb-free PDIPs can be used for through hole wave solder

processing only. They are not intended for use in Reflow solder

processing applications.

V-

REFERENCE

NALOG COMMON

INT OUT

AZ IN

BUFF OUT

REF CAP -

REF CAP +

IN LO

IN HI

V+

(MSD) D5

(LSB) B1

B2

UNDERRANGE

STROBE

R/H

DIGITAL GND

POL

BUSY

D2

D3

D4

(MSB) B8

B4

OVERRANGE

CLOCK IN

(LSD) D1

28

27

26

25

24

23

22

21

20

19

18

17

16

15

1

2

3

4

5

6

7

8

9

10

11

12

13

14

Data Sheet

October 25, 2004

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 321-724-7143

Copyright Intersil Americas Inc. 2000, 2004. All Rights Reserved

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