A Functional Circuits Design of Variable Frequency Switching type DC-DC Converter Integrated Circuit

Abstract

This paper describes functional circuits of DC-DC converter IC incorporated with variable frequency PFM technique. In case of output voltage of DC-DC converter is reached setting value or output current is low then PFM switching frequency is slow down. In this work a PFM signal generator, a PFM Frequency Control Circuit, an output voltage detector and an over current protection circuits are designed. This device has been designed at a 0.35 [㎛], double poly, double metal 12[V] CMOS process.