© 2006 Microchip Technology Inc.

DS21457C-page 7

TC7116/A/TC7117/A

34

42

used, a 1

μF capacitor is recommended and will hold the rollover error to

0.5 count.

35

43

V+

Positive Power Supply Voltage.

36

44

The analog input required to generate a full scale output (1999 counts). Place

100mV between Pins 32 and 36 for 199.9mV full scale. Place 1V between

Pins 35 and 36 for 2V full scale. See Section 4.6 “Reference Voltage”, Refer-

ence Voltage.

37

3

TEST

Lamp test. When pulled HIGH (to V+), all segments will be turned on and the dis-

play should read -1888. It may also be used as a negative supply for externally

generated decimal points. See Section 3.1.7 “Test”, TEST for additional infor-

mation.

38

4

OSC3

See Pin 40.

39

6

OSC2

See Pin 40.

40

7

OSC1

Pins 40, 39, 38 make up the oscillator section. For a 48kHz clock (3 readings per

section), connect Pin 40 to the junction of a 100k

Ω resistor and a 100pF capaci-

tor. The 100k

Ω resistor is tied to Pin 39 and the 100pF capacitor is tied to Pin 38.

TABLE 2-1:

PIN FUNCTION TABLE (CONTINUED)

Pin Number

(40-Pin PDIP)

(40-Pin CERDIP)

Pin Number

(44-Pin PQFP)

Symbol

Description