The HD66766R, color-graphics LCD controller and driver LSI, displays 132-by-176-dot graphics for 65K STN colors. A 16-bit high-speed bus interface and high-speed RAM write function enable efficient data transfer and high-speed rewriting of data to the graphics RAM. The HD66766R has various functions for reducing the power consumption of a LCD system, such as low-voltage operation of 2.2 V/min., a step-up circuit to generate a maximum of 12-times the LCD drive voltage from the supplied voltage, and voltage-followers to decrease the direct current flow in the LCD drive bleeder-resistors. Combining these hardware functions with software functions, such as a partial display with low-duty drive and standby and sleep modes, allows precise power control. The HD66766R is suitable for any mid-sized or small portable battery-driven product requiring long-term driving capabilities, such as digital cellular phones supporting a WWW browser, bi-directional pagers, and small PDAs.