ST

Sitronix

ST7556

65 x 102 Dot Matrix LCD Controller/Driver

Ver 2.2

1/43

2005/10/05

1. INTRODUCTION

The ST7556 is a driver & controller LSI for graphic dot-matrix liquid crystal display systems. It contains 102 segment

and 65 common with 1 ICOM driver circuits. This chip is connected directly to a microprocessor, accepts 4-line serial

interface (SPI) or 8-bit parallel interface, display data can store in an on-chip display data RAM of 66 x 102 bits. It

performs display data RAM read/write operation with no external operating clock to minimize power consumption. In

addition, because it contains power supply circuits to drive liquid crystal, it is possible to make a display system with the

fewest components.

2. FEATURES

Driver Output Circuits

102 segment outputs / 65+1 common outputs

On-chip Display Data ram

-

Capacity: 66X102=6,732 bits

Microprocessor Interface

-

8-bit parallel bi-directional interface with

6800-series or 8080-series

-

4-line SPI (serial peripheral interface) available

(only write operation)

On-chip Low Power Analog Circuit

-

Generation of LCD supply voltage (externally

Vout voltage supply is possible)

-

Generation of intermediate LCD bias voltages

-

Oscillator requires no external components

(external clock also possible)

-

Voltage converter (x4)

-

Voltage regulator (temperature gradient

-

Voltage follower

-

On-chip electronic contrast control function (128

steps)

-

Liquid crystal driving voltage :

V0 -VSS = max 12 V (external power supply)

External RESB (reset) pin

-

1.8 to 3.3V

Temperature range: -30 to +85 degree