Designing an Efficient Rail-to-Rail Class AB Amplifier as Buffer In LCD

摘要

For enhancing the high color depth and to provide higher resolution for LCD signal driver. This paper proposes a complementary differential amplifier with offset voltage cancellation technique. In order to improve the offset cancellation ability the complementary differential pairs are separated into main and auxiliary transconductance amplifiers. This achieves Rail-to-Rail output swing. In the proposed method offset cancellation is achieved by dividing offset cancellation and driving phases with the help of three switches. With this proposed architecture the offset voltage is reduced from 8.9 mV to 0.3 mV, which is a considerable amount of reduction. It is also observed that CMRR and Slew rate are not affected with the proposed technique.