The LH155BA is an LCD driver with a built-in RAM suitable for driving medium/small scale dot-matrix LCD panels, and which is capable of being directly connected to the bus line of a microcomputer. The LH155BA stores in the RAM the 8-bit parallel or serial display data transferred from the microcomputer and generates LCD drive signals. Since the LH155BA features a bit-map type LCD driver that one bit of data in the display RAM corresponds to one dot in the LCD, there is a lot of freedom in displaying. The LH155BA has 128 segment outputs and 64 common outputs in a single chip, making it possible to create an LCD system with the fewest number of the chips. The LH155BA enables an LCD system for batteryoperated, hand-carrying information equipment by securing lower power consumption and wider operating voltage range.