INTRODUCTION
The ST7687S is a driver & controller LSI for 65K color graphic dot-matrix liquid crystal display systems. It generates 384 Segment and 128 Common driver circuits. This chip is connected directly to a microprocessor, accepts Serial Peripheral Interface (SPI) or 8-bit parallel display data and stores in an on-chip display data RAM. 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 necessary to drive liquid crystal, it is possible to make a display system with the fewest components.

FEATURES
Driver Output Circuits
   ♦ 384 segment outputs / 128 common outputs
Applicable Duty Ratios
   ♦ Various partial display
   ♦ Partial window moving & data scrolling
Gray-Scale Display
   ♦ 4FRC & 31 PWM function circuit to display 64
      gray-scale display
   ♦ Support 8 color mode (Idle mode)
On-chip Display Data RAM
   ♦ Capacity: 128 x 128 x 16 =262,144 bits
Color support by Interface
   ♦ 4k colors (RGB)=(444) mode
   ♦ 65K colors (RGB)=(565) mode
Microprocessor Interface
   ♦ 8 bit parallel bi-directional interface with 6800-series or
      8080-series
   ♦ 4-line serial interface
   ♦ 3-line (9-bits) serial interface

On-chip Low Power Analog Circuit
   ♦ On-chip oscillator circuit
   ♦ Voltage converter (x2~x8) with internal capacitors.
   ♦ Extremely Few Outsider Components.
   ♦ On-chip Voltage Regulator
   ♦ On-chip electronic contrast control function
   ♦ Voltage follower (LCD bias: 1/6~1/12)
Operating Voltage Range
   ♦ Supply Digital Voltage (VDD): 1.65 to 3.3V
   ♦ Supply Analog Voltage (VDD2~VDD5): 2.4 to 3.3V
   ♦ LCD driving voltage (VOP = V0 - VSS): Max: 18V
LCD Driving Voltage
   ♦ Contrast Adjustment Value is stored in the Built-In
      EEPROM for better display quality.
LCD Driving setting suggestion
   ♦ VOP = 14V, BIAS=1/9. (VDD=2.8V)
Package Type
   ♦ Application for COG