A non-isolated 650W DC-DC converter using a novel buck-boost topology with two low-side MOSFETs

This article presents a non-isolated 650W DC-DC converter with an input voltage range of 150V until 700V. A novel buck-boost topology with two low-side MOSFETs was designed by combining the classical buck topology and boost topology. This novel topology configuration has an advantage in selecting gate driver integrated circuit (IC), since the IC does not need to provide high-side gate signals. To control gate signals of the two low-side MOSFETs, a new analog control circuitry was proposed and implemented. A 290V output voltage and 650W output power prototype were fabricated to evaluate the effectiveness of the proposed converter. The measurements are validated a peak efficiency of 98.11% in boost mode and 97.45% in buck mode at a switching frequency of 100kHz.