4 1/2-DIGIT PRECISION

ANALOG-TO-DIGITAL CONVERTERS

D Zero Reading for 0-V Input

D Precision Null Detection With True Polarity

at Zero

D 1-pA Typical Input Current

D True Differential Input

D Multiplexed Binary-Coded-Decimal (BCD)

Output

D Low Rollover Error: ±1 Count Max

D Control Signals Allow Interfacing With

UARTs or Microprocessors

D Autoranging Capability With Over-and

Under-Range Signals

D TTL-Compatible Outputs

D Direct Replacement for Teledyne TSC7135,

Intersil ICL7135, Maxim ICL7135, and

Siliconix Si7135

D CMOS Technology

description

The HT7135A and TLC7135A converters are manufactured with Htcsemi Instruments highly efficient

CMOS technology. These 4 1/2-digit, dual-slope-integrating, analog-to-digital converters (DACs) are

designed to provide interfaces to both a microprocessor and a visual display. The digit-drive outputs D1

through D4 and multiplexed binary-coded-decimal outputs B1, B2, B4, and B8 provide an interface

for LED or LCD decoder/drivers as well as microprocessors.

The HT7135A and TLC7135A offer 50-ppm (one part in 20,000) resolution with a maximum linearity error of

one count. The zero error is less than 10

µV and zero drift is less than 0.5 µV/°C. Source-impedance errors are

minimized by low input current (less than 10 pA). Rollover error is limited to

±1 count.

The BUSY, STROBE, RUN/HOLD, OVER RANGE, and UNDER RANGE control signals support

microprocessor-based measurement systems. The control signals also can support remote data acquisition

systems with data transfer through universal asynchronous receiver transmitters (UARTs).

The HT7135A and TLC7135A are characterized for operation from 0

°C to 70°C.

AVAILABLE OPTIONS

PACKAGE

TA

PLASTIC DIP

(N)

SMALL OUTLINE

(DW)

0

°Cto70°C

TLC7135ANZ

0

°C to 70°C

1

2

3

4

5

6

7

8

9

10

11

12

13

14

28

27

26

25

24

23

22

21

20

19

18

17

16

15

VCC–

REF

ANLG COMMON

INT OUT

AUTO ZERO

BUFF OUT

Cref–

Cref+

IN –

IN +

VCC+

D5

B1

B2

UNDER RANGE

OVER RANGE

STROBE

RUN/HOLD

DGTL GND

POLARITY

CLK

BUSY

D1

D2

D3

D4

B8

B4

DW OR N PACKAGE

(TOP VIEW)

TLC7135ARTZ

HT7135ANZ

HT7135ARWZ

Rev. 00

HT7135A

TLC7135A

HT7135A

TLC7135A