P-54: A Single-Inductor Bipolar-Output Converter with Power Conservation Mechanism (PCM) for Driving Cholesteric LCD

Cholesteric liquid‐crystal display (Ch‐LCD) has the bi‐stable characteristic to achieve the energy‐saving for the green technology. Backlight is even unnecessary in the Ch‐LCD system. The single‐inductor bipolar‐output (SIBO) converter is one of best candidate to supply the power management function for the Ch‐LCD with dual positive and negative output voltages by using a single inductor for a compact solution. The energy control methodology with the current‐mode control and the power conservation mechanism (PCM) can strengthen the voltage quality to get high display quality. The test chip fabricated by 0.25 μm CMOS technology demonstrates the non‐noticeable cross‐regulation at dual outputs with 90 % peak power conversion efficiency.