INTRODUCTION

ST7541  is  a  driver  &  controller  LSI  for  4-level  gray  scale  graphic  dot-matrix  liquid  crystal  display  systems.  This  chip  can connect directly to a microprocessor which supports: Serial Peripheral Interface (SPI), IIC or 8-bit parallel interface. Display data stores in an on-chip display data RAM of 128 x 129 x 2 bits. It performs display data RAM read/write operation with no external operating clock to minimize power consumption.

FEATURES

4-level Gray Scale

–Display with PWM and FRC Methods

Driver OutputCircuits

  128 segment outputs/ 128+1 common outputs

ApplicableDutyRatios

– V arious partial display

–Partial window moving & data scrolling

On-chipDisplay Data RAM

–Capacity: 128  ×  129  ×  2=33,024 bits

Microprocessor Interface

–  8-bit  bi-directional  parallel  interface  supports  6800-series or 8080-series MPU

– 4-line serial interface(4-LineSPI)

– 3-line serial interface(3-Line 8-bit SPI)

– IIC serial interface

On-chip Low PowerAnalogCircuit

– On-chip oscillator circuit

– Voltage booster (x3, x4, x5 or x6)

– Voltageregulator (temperature coefficient: -0.144%/˚C, or external input)

– On-chip electronic contrast controlfunction(64 steps X 8)

– Voltage follower (LCD bias: 1/5to 1/12)

Operating V oltage Range

–Supply voltage(VDD): 1.8to 3.3V

–Supply voltage(VDD2): 2.4 to 3.3V

– LCD driving voltage(VLCD =V0- VSS): 3.5 to 15.0V Package Type

–  Applicationfor COG