¡ Semiconductor

MSM9004-01/02

6/15

PIN DESCRIPTIONS

Pin

Symbol

Type

Connected to

Description

CLOCK1

OSC

DATA

CLOCK2

LOAD

BLANK

3/4SEL

COM1-4

SEG1-49

56

I

Micro-

controller

56

I

External

resistor

Capacitor

52

I

Micro-

controller

51

I

Micro-

controller

53

I

Micro-

controller

50

I

54

I

61 to 64

O

LCD

1 to 49

O

LCD

60

Power

supply

55

Power

supply

59

57

58

OSC

—

—

—

—

1

*1

*2

System clock input pin.

For details, see "MSM9004-02 Oscillation Circuit Characteristics".

Pin for oscillation.

Connecting the external resistor and capacitor to

configure the oscillation circuit.

Connect the resistor and capacitor as shown in the

right figure.

Make the length of wiring between this pin and the

external resistor and capacitor as short as passible.

Serial data input.

For details on the configuration of input data, see "Data Configuration".

Shift clock input (Schmitt circuit included).

Input data is read synchronizing with the rising edge of this clock.

Load signal input (Schmitt circuit included).

Serial input data is transferred to the display latch when this LOAD

signal is at a "H" level.

Input pin for turning off all segments.

All segments turn off, regardless of the display data, when this pin is

at a "L" level, and all segments return to the status before turning off.

Input pin for selecting 1/3 or 1/4 duty.

1/3 duty drive is selected when this pin is at a "H" level, and 1/4 duty

drive is selected when this pin is at a "L" level.

LCD common outputs.

Leave COM4 open for 1/3 duty drive.

LCD segment outputs.

Bias power supply pins for driving the LCD.

Conditions for bias voltage are as follows :

Power supply pins.

2

*1: Applied to MSM9004-01.

*2: Applied to MSM9004-02.