COM voltage generator that supports both real-time updating as well as multibyte storage of gamma/VCOM data in on-chip EEPROM memory. An independent 10-bit DAC, two 10-bit data registers, and four words of EEPROM memory are provided for each individually addressable gamma or VCOM channel. High-performance buffer amplifiers are integrated on-chip, providing rail-to-rail, low-power (400µA/gamma channel) operation. The VCOM channel features a high current drive (> 250mA peak) and a fast-settling buffer amplifier optimized to drive the VCOM node of a wide range of TFT-LCD panels.
Programming occurs through an I²C-compatible serial interface. Interface performance and flexibility are enhanced by a pair of independently loaded data latches per channel, as well as support for I²C speeds up to 400kHz. The multitable EEPROM memory enables a rich variety of display system enhancements, including support for temperature or light-level dependent gamma tables, enabling of factory or field automated display adjustment, and support for backlight dimming algorithms to reduce system power. Upon power-up and depending on mode, DAC data is selected from EEPROM by the S0/S1 pins or from a fixed memory address.