Research And Design Of Multichannel Power Management Unit For Portable Products

With the fast growth of information technology, the system integration becomes higher and higher. A lot of systems originally used the discrete solutions now change to use the integrated chips. PMU (Power Management Unit), a highly integrated power management solution, mainly targets the portable applications. It integrates the conventional discrete power management solutions into one single package. It helps to increase the system power efficiency, reduce the space of the board and etc. PMU has been a trend for the future power management chips, as it is very important for the industry and the customers. The idea of application processor plus PMU has been well recognized by the industry, the large multi-national companies like TI, NXP, Maxim, ADI and etc have released many PMU products.The thesis firstly introduces the system of the PMU and its basic blocks, also the difference compare to the conventional power management chips. After that, the thesis mainly focuses on two important channels inside the PMU, one is the high efficiency low quiescent current buck regulator, including the efficiency analysis under heavy load and the three control scheme in light load, extended on time PFM control, low quiescent current PFM control and average current PFM control; the second one is the high accuracy LED constant current boost driver, analysis the boost regulator design as well as the accurate current control scheme for both low side sink current control and high side source current control.The thesis is based on three silicon proved chips; one is the9-channel PMU for single cell application in TSMC0.35um BCD5V/20V process, the second one is the12-channel PMU for multi-cell application in TSMC0.35um BCD5V/20V process, the third one is the15-channel PMU for single and dual cell application in TSMC0.18um BCD5V/40V process.