Pad Description

Pad No.

Pad Name

I/O

Description

1

LOWC

B

For low voltage detector, open the pin when not in use.

2

VSS

I

Power supply GND

3

SC

B

Common point, NMOS open drain

4

RF

O

Connect reference resistor, PMOS open drain

5

RS

O

Connect sensor resistor, PMOS open drain

6

VDD

I

Power supply positive

7

PSW

I

Pull-low input pin, press switch to turn the power on or off

8TEST2

I

Pull-low test pin, for production, floating test, LCD displays

the real time value, when connected to VDD, LCD displays

the highest value.

9

CLFH

I

Connecting VSS for

°C, connect to VDD for °F

10

OSCI

I

For system oscillator in

11

OSCO

O

For system oscillator out

12

BZ1

O

Buzzer output 1

13

BZ2

O

Buzzer output 2

14

EN

O

Interface with HT84018-0D

15

DATA

O

Interface with HT84018-0D

16

READY

O

Interface with HT84018-0D

17

BUSY

I

Interface with HT84018-0D

18~20

COM1~COM3

O

LCD backplane drive, 3 level voltage out

21~23

SA1~SA3

O

LCD segment drive

24~26

SB1~SB3

O

LCD segment drive

27~29

SC1~SC3

O

LCD segment drive

30

SD1

O

LCD segment drive

31

CAP15V

O

1.5V output for LCD display

32

C512

O

Test pin for IC (512Hz output)

33

TV

B

Test pin for IC

34

TEST1

I

Test pin for IC

35

TTM

I

Test pin for IC

36

TS816

I

Test pin for IC

HT7510

4

10th Feb ’99