Adaptive Dead-time Control Circuit Based on GaN Device Buck Converter
This study proposes an adaptive dead-time control circuit for a buck converter driven by GaN devices.The circuit determines the dead-time duration by detecting the duration and magnitude of the negative voltage at switch nodes and achieves adaptive adjustment of the dead-time duration through negative feedback.The optimal dead-time duration for the rising and falling edges of the switch node voltage can reach 0 and 0.7 ns,respectively.This dead-time control circuit achieves high-precision sub-nanosecond dead-time control and can rapidly start and dynamically adjust the dead-time duration when the output load of the buck converter changes.The circuit includes a load step protection module,which can rapidly reset the dead-time duration when the rapid load decrease of the buck converter is detected,ensuring the safe operation of GaN power devices.The adaptive dead-time control technology is added to a 12 V to 1 V buck converter.The conversion efficiency of the buck converter can be improved by up to 3.7％compared with constant dead-time control.
万方数据
维普
