Wide temperature operation of a PWM DC-DC convertor

Wide temperature electronics is of great interest for space exploration programs. In this study, the wide temperature (-185/spl deg/C to 200/spl deg/C) operation of a 150 W, 50 kHz, 24/48 V pulse-width modulated (PWM) boost DC-DC power converter is reported. The power MOSFET, the power rectifier and the input inductor were placed inside a temperature chamber, whereas the rest of the power and control circuitry as well as all measuring instruments were at room temperature. The power converter efficiency varied between 92.2% and 89.4% in the entire temperature range. The power MOSFET loss decreased with decreasing temperatures. For the diode rectifier, loss increased with decreasing as well as increasing temperatures compared to room temperature operation. The inductor loss also increased due to increasing as well as decreasing temperatures compared to room temperature operation. Overall, the power converter operated successfully in a wide temperature range designed with commercially available components. Wide temperature operation of power capacitors and control circuitry, and the relevant reliability issues for passive and active components are to be addressed for design and operation of wide temperature electronic systems.