FEDL9471-01

LAPIS Semiconductor

ML9471

4/20

PIN DESCRIPTION

Symbol

Type

Description

OSC_IN

OSC_OUT

OSC_OUT

I

O

O

Pins for oscillation.

The oscillator circuit is configured by externally connecting two

resistors and a capacitor.

Make the wiring length as short as possible, because

the resistor connected to the OSC_IN pin has a higher value and the circuit is

susceptible to external noise.

DATA_IN

I

Serial data input pin. The display goes on when input data is at a “H” level, and it

goes off when input data is at “L” level.

CLOCK

I

Shift clock input pin.

Data from the DATA_IN pin is transferred in synchronization

with the rising edge of the shift clock.

LOAD

I

Load signal input pin.

Serially input data is transferred to the 80-bit latch at “H”

level of this load signal, then held at “L” level.

BLANK

l

Input pin that turns off all segments.

The entire display goes off when “L” level is

applied to this pin.

The display returns to the previous state when “H” level is

applied.

DSEL1

DSEL2

I

I

Input pins to select 1/3, 1/4, or 1/5 duty.

Following shows how each duty is

selected.

DSEL2

DSEL1

Duty selected

L

L

1/3

L

H

1/4

H

X

1/5

X: Don’t care

COM1 to

COM5

O

Display output pins for LCD.

These pins are connected to the COMMON side of

the LCD panel.

SEG1 to

SEG80

O

Display output pins for LCD.

Theses pins are connected to the SEGMENT side of

the LCD panel.

For the correspondence between the output of these pins and

input data, see the “Data Structure” Section.

—

Bias pins for LCD driver. Through these pins, bias voltages for the LCD are

externally supplied.

The bias potential must meet the following condition:

—

Supply voltage pin and ground pin.

Note: Built-in schmitt circuit is used for all input pins.