How to Design an Efficient DC-DC Converter Using the DS1875 PWM Controller

Abstract: The DS1875 features a pulse-width modulation (PWM) controller that can be used to control a DC-DC converter. The DC-DC converter can then be used to generate the high bias voltages necessary for avalanche photodiodes (APDs). This application note describes the operation of a boost converter that uses the DS1875. Discussion covers the selection of the inductor and switching frequency, and the selection of components that improve the efficiency of the converter. Test data are presented.