An intergrated DC-DC converter with digital one-step dead-time correction

This paper presents an integrated 6V to 1V, 3W DC-DC converter with a novel one-step dead-time digital controller designed for 40V 0.25μm CMOS technology. The proposed one-step digital control scheme can continuously optimize the dead-times for the turn-on and turn-off of the power MOSFETs. Comparing with previously reported dead-time optimization techniques, this work can achieve quick and accurate adjustment of the dead-time with minimum chip area overhead. A 10-bit hybrid DPWM modulation circuit, a NOR gate and a level shifter circuit are integrated with the output stage to detect and measure the duration of the unwanted low-side MOSFET body-diode conduction. Experimental results shows a 1% to 5% power conversion efficiency improvement.