A multi-level multi-phase charge-recycling method for low-power AMLCD column drivers

This paper describes a new low-power design concept appropriate for column drivers of high-resolution active matrix liquid crystal displays with a dot inversion method. The proposed multi-level multiphase charge-recycling met hod reduces power consumption incurred in driving highly capacitive column lines by storing the charge into the external capacitors and reusing it in the next cycle, With the proposed method, power consumption can be reduced asymptotically to zero with the infinite number of storage capacitors. Howe ver, it is also shown that total power reduction can be counterbalanced by the power consumption in driving switches used in the recycling process. An alytical equations, simulation results, and measurement results from an exp erimental chip are shown to validate the proposed method. Dynamic power red uction of 55%-70% is measured with a three-level five-phase charge-recyclin g method compared with a conventional column driver.