We propose the dynamic power MOS width controlling technique and the adaptive gate driver voltage technique to find out the better approach to power saving in DC-DC converters. It demonstrates that the dynamic power MOS width controlling technique has much improvement in power consumption than that of the adaptive gate driver voltage technique when the load current is heavy or light. After the dynamic power MOS width modification, the simulation results show that the efficiency of current-mode DC-DC buck converter can be improved from 92% to about 98% in heavy load and from 15% to about 16.3% in light load. However, the adaptive gate driver voltage technique has only little improvement of power saving. It means that the dynamic width controller is the better approach to power saving in the DC-DC converter.
['Hung-Chi Lee', 'Kuo-Tai Chang', 'Ke-Horng Chen', 'Wen Tsao Chen']
Power saving of a dynamic width controller for a monolithic current-mode CMOS DC-DC converter