The ST7541 is a driver & controller LSI for 4-level gray scale graphic dot-matrix liquid crystal display systems. This chip is connected directly to a microprocessor, accepts Serial Peripheral Interface (SPI),IIC or 8-bit parallel display data and 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. 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.
Microprocessor Interface -- 8-bit parallel bi-directional interface with 6800-series or 8080-series -- 4-line serial interface (4-line-SIF) -- 3-line serial interface (3-line-SIF) -- IIC serial interface
On-chip Low Power Analog Circuit -- On-chip oscillator circuit -- Voltage converter (x3, x4, x5 or x6) -- Voltage regulator (temperature coefficient: -0.125%/ C, or external input) -- On-chip electronic contrast control function (64 steps X 8) -- Voltage follower (LCD bias : 1/5 to 1/12)
Operating Voltage Range -- Supply voltage (VDD): 1.8 to 3.3V -- LCD driving voltage (VLCD = V0 - VSS): 4.0 to 15.0 V