An 8-bit Digital Data Driver for AM-LCDs Using an Alternating Voltage Drive Method

Abstract

Devices and structures to resolve the issues of (1) die-size, (2) output deviations, and (3) power dissipation on an 8-bit digital data driver for AM-LCDs using an Alternating Voltage Drive (AVD) Method are reported. As voltage interpolation is performed by logical circuit in the AVD Method, device has been applied in the mechanism of determining the waveform in the voltage interpolative circuit and consequently the number of logical gates of an interpolative circuit has become less than that of a 6-bit driver. Concerning the output deviations, voltage deviations originated from line resistances are compensated by paired structures of voltage providing lines. This realized the output deviation characteristics that is less than half of the 6-bit driver. In order to suppress the increase of power dissipation, the frequency of the alternating voltage is increased gradually by 3 stages; thus, the 8-bit module has nearly same power dissipation as the 6-bit module.