A Low Power Zero Current Detector for Synchronous Buck Converter

This paper proposes a low power dissipation zero current detector (ZCD) for synchronous buck converter. The ZCD circuit has simple structure and low power consumption. In the proposed ZCD circuit, some auxiliary devices of the comparator and a bias voltage setting circuit can further reduce the average power dissipation of the circuit, and a delay blanking circuit can avoid the false flip caused by the ZCD. Based on a 180 nm BCD process, the simulation results show that quiescent current of the proposed ZCD is about 5.7μA, and the false flip of ZCD can be eliminated to ensure the normal operation of the buck converter.