3-208

TELCOM SEMICONDUCTOR, INC.

TC7116

TC7116A

TC7117

TC7117A

PIN DESCRIPTION (Cont.)

40-Pin CerDIP

44-Pin

40-Pin PDIP

Plastic Quad

Pin Number

Flat Package

Normal

Pin Number

Symbol

Description

33

41

C

–

REF

See pin 34.

34

42

C

+

REF

A 0.1

µF capacitor is used in most applications. If a

not at analog common), and a 200 mV scale is used, a 1

µF capacitor is recommended and will hold the roll-over

error to 0.5 count.

35

43

Positive power supply voltage.

36

44

V

+

REF

The analog input required to generate a full-scale output

(1999 counts). Place 100 mV between pins 32 and 36

for 199.9 mV full scale. Place 1V between pins 32 and

36 for 2V full scale. See paragraph on Reference

Voltage.

37

3

TEST

be turned on and the display should read –1888. It may

also be used as a negative supply for externally-

generated decimal points. See Test paragraph for more

details.

38

4

See pin 40.

39

6

See pin 40.

40

7

Pins 40, 39 and 38 make up the oscillator section. For

a 48 kHz clock (3 readings per sec), connect pin 40 to

the junction of a 100 k

Ω resistor and a 100 pF capacitor.

The 100 k

Ω resistor is tied to pin 39 and the 100 pF

capacitor is tied to pin 38.

3-1/2 DIGIT ANALOG-TO-DIGITAL

CONVERTERS WITH HOLD