INTRODUCTION
The ST7531 is a driver & controller LSI for 65K color graphic dot-matrix liquid crystal display systems. It generates 256 Segment and 160 Common driver circuits. This chip is connected directly to a microprocessor, accepts Serial Peripheral Interface (SPI), 8-bit/16-bit parallel or IIC display data and stores in an on-chip display data RAM. It performs display data RAM read/write operation with no external operatingclock to minimize power consumption. In addition, because it contains power supply circuits necessary to drive liquid crystal, it is possible to make a display system with the fewest components.

FEATURES
Driver Output Circuits
−256 segment outputs / 160 common outputs
−Maximum resolution is 170(SPRD) x 160.
Applicable Duty Ratios
− Various partial display
− Partial window moving & data scrolling
Microprocessor Interface
− 8/16-bit parallel bi-directional interface with 6800-series
or 8080-series
−4-line serial interface (write only)
−9 bit 3-line serial interface (write only)
On-chip Display Data RAM
− Capacity : 160 x 256 x 5bit = 204800bits (Max)
On-chip Low Power Analog Circuit
− On-chip oscillator circuit
− Voltage converter (x2, x3, x4, x5, x6, x7, x8)
− Voltage regulator
− Voltage follower 
(LCD bias: 1/5, 1/7, 1/9, 1/10, 1/11, 1/12, 1/13, 1/14)
Operating Voltage Range
− Supply voltage 
(VDD, VDD1, VDD2, VDD3, VDD4, VDD5): 2.4 to 3.3V
− LCD driving voltage (VLCD = V0 - VSS): 3.76 to 18.0 V
Temperature Gradient Coefficient
; −  -0.130%/℃ +/-10%
LCD driving voltage (EEPROM) 
− To store contrast adjustment value for better display
Package Type
− Application for COG