A 10 MHz mixed-signal CPM controlled DC-DC converter IC with novel gate swing circuit and instantaneous efficiency optimization

Abstract

This paper introduces a mixed-signal peak current-programmed mode controlled 10 MHz dc-dc converter integrated circuit (IC) for low-power applications. The IC combines segmented power transistors, gate drivers and the main functional blocks of a multi-mode controller. Based on the information about the peak transistor current, obtained from the voltage loop, the controller instantaneously changes the number of segments, gate drive voltage, or switches to pulse-frequency modulation, such that for each operating point efficiency is optimized. To obtain reliable operation at such a high switching frequency and achieve efficiency optimization novel architecture of gate swing circuit is combined with modifications of known designs of other functional blocks. Experimental verification of a 0.6 W buck converter IC, fabricated in a 0.13 μm process, demonstrate the peak efficiency of an 83%, near time-optimal dynamic response, and up to a 20% efficiency improvement due to the action of the efficiency optimization controller.