3-31

August 1997

ICL7129

Single-Chip A/D Converter

Features

•

±19,999 Count A/D Converter Accurate to ±4 Count

•10

µV Resolution on 200mV Scale

• 110dB CMRR

• Direct LCD Display Drive

• True Differential Input and Reference

• Low Power Consumption

• Decimal Point Drive Outputs

• Overrange and Underrange Outputs

• Low Battery Detection and Indication

• 10:1 Range Change Input

Description

analog-to-digital converter that directly drives a multiplexed

liquid crystal display. This single chip CMOS integrated cir-

cuit requires only a few passive components and a reference

to operate. It is ideal for high resolution hand-held digital

multimeter applications.

The performance of the ICL7129 has not been equaled

before in a single chip A/D converter. The successive integra-

tion technique used in the ICL7129 results in accuracy better

than 0.005% of full scale and resolution down to 10

µV/count.

The ICL7129, drawing only 1mA from a 9V battery, is well

suited for battery powered instruments. Provision has been

made for the detection and indication of a “LOW/BATTERY”

condition. Autoranging instruments can be made with the

ICL7129 which provides overrange and underrange outputs

and 10:1 range changing input. The ICL7129 instantly checks

for continuity, giving both a visual indication and a logic level

output which can enable an external audible transducer. These

features and the high performance of the ICL7129 make it an

extremely versatile and accurate instrument-on-a-chip.

Pinouts

Ordering Information

PART NUMBER

TEMP.

PACKAGE

PKG. NO.

ICL7129CPL

0 to 70

40 Ld PDIP

E40.6

ICL7129RCPL

0 to 70

40 Ld PDIP

E40.6

ICL7129CM44

0 to 70

44 Ld MQFP

Q44.10x10

NOTE: “R” indicates device with reversed leads.

ICL7129 (PDIP)

TOP VIEW

ICL7129 (MQFP)

TOP VIEW

13

1

2

3

4

5

6

7

8

9

10

11

12

14

15

16

17

18

19

20

OSC1

OSC3

ANNUNCIATOR

BP3

BP2

BP1

28

40

39

38

37

36

35

34

33

32

31

30

29

27

26

25

24

23

22

21

OSC2

RANGE

DGND

REF LO

REF HI

IN HI

IN LO

BUFF

COMMON

CONTINUITY

INT OUT

INT IN

V+

V-

LATCH/HOLD

DRIVE

OSC 1

OSC 2

RANGE

DGND

1

2

3

4

5

6

7

8

9

10

11

12 13 14 15 16 17

OSC 3

NC

NC

ANNUNCE

28

27

26

25

24

23

22

21

20

19

18

BP3

BP2

BP1

39 38 37 36 35 34

33

32

31

30

29

44 43 42 41 40

V+

V-

NC

NC

LATCH/

DRIVE

HOLD

File Number

3085.1

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

http://www.intersil.com or 407-727-9207