Pin Functions

No. 6235-5/14

LC75844M

CE: Chip enable

CL:

Synchronization clock

DI:

Transfer data

H

—

S1/P1 to

S4/P4

S5 to S22

Pin

1 to 4

5 to 22

—

O

Open

Segment outputs for displaying the display data transferred by serial data input. The pins

S1/P1 to S4/P4 can be used as general-purpose output ports when so set up by the

control data.

COM1

COM2

COM3

COM4

23

24

25

26

—

O

Open

Common driver outputs.

OSC

32

CE

CL

DI

34

35

36

Serial data transfer inputs. These pins are

connected to the control microprocessor.

—

I/O

I

GND

Oscillator connection

An oscillator circuit is formed by connecting an external resistor and capacitor to this pin.

29

—

I

Open

Used to apply the LCD drive 2/3 bias voltage externally. This pin must be connected to

30

—

I

Open

Used to apply the LCD drive 1/3 bias voltage externally. This pin must be connected to

27

——

—

Logic block power supply. Provide a voltage in the range 2.7 to 6.0 V.

28

——

—

LCD driver block power supply. Provide a voltage in the range 2.7 to 6.0 V.

31

——

—

Ground pin. Connect to ground.

INH

33

L

I

GND

Display off control input

Off

S1/P1 to S4/P4 = Low

(These pins are forcibly set to the segment output port function and

Note that serial data transfers can be performed when the

display is forced off by this pin.

Active

I/O

Handling

when unused

Function

Pin No.

Serial Data Transfer Format

1. When CL is stopped at the low level

Note: DD ... Direction data

CE

CL

DI

A12600

00100010

B0 B1 B2 B3 A0 A1 A2 A3

D1

D2 D3

D37 D38 D39 D40 D41 D42 D43 D44 00000

P0 P1 P2 DR SC BU

0

00100010

B0 B1 B2 B3 A0 A1 A2 A3

D45 D46 D47

D81 D82 D83 D84 D85 D86 D87 D88 000000000001

CCB address

8 bits

CCB address

8 bits

Display data

44 bits

Display data

44 bits

Control data

11 bits

Fixed data

11 bits

DD

1 bit

DD

1 bit