Design of reference voltage source integrated in LCoS chip

This paper proposes the design of programmable multi-channel reference voltage source integrated in LCoS chip, analyses the role of reference voltage in LCoS display system. Emphasis was placed on the design of analog circuits which consist of dual ladder resistor D/A converter and constant gm rail-to-rail operational amplifier. The reference voltage source for gamma correction of LCoS display is taped out by Chartered 0.35 μm CMOS 2P4M Mixed-mode process, and the chip was tested. The test results indicate that the output of the chip can completely meet requirements of the common electronic field-inversion field sequential LCoS display system, and the setup time and accuracy of output voltage achieve the expected target.