公开(公告)号：US20010046145A1

公开(公告)日：2001-11-29

申请号：US09814237

申请日：2001-03-21

Applicant: International Rectifier Corp.

Inventor： V. Stepan Oknaian ,  J. Steven Brown

IPC: H02M003/24

CPC classification number: H02M3/156 ,  H01L2924/19043 ,  H02M3/1588 ,  H02M2001/0009 ,  Y02B70/1466

Abstract: A circuit and method for sensing the inductor current flowing to a load from a switching power supply without using a sense resistor in the path of the inductor current. In a synchronous buck converter topology, the inductor current is derived by sensing the voltage drop across the synchronous MOSFET of the half-bridge and reconstructing the current using a sample and hold technique. A ripple current synthesizer is employed to reconstruct inductor current outside the sample and hold window. The sampled product ILoadnullRDSon is used to update the ripple current estimator with dc information every switching cycle. The resulting voltage waveform is directly proportional to the inductor current. The inductor current synthesizer of the present invention can also be used in boost converter, flyback converter and forward converter topologies.

Abstract translation: 一种用于感测从开关电源流向负载的电感器电流而不在电感器电流的路径中使用检测电阻器的电路和方法。 在同步降压转换器拓扑中，通过感测半桥的同步MOSFET上的电压降并通过采样和保持技术来重建电流来导出电感电流。 纹波电流合成器用于重建样品和保持窗外的电感电流。 采样产品ILoadxRDSon用于每个切换周期用直流信息更新纹波电流估计器。 所产生的电压波形与电感电流成正比。 本发明的电感器电流合成器也可用于升压转换器，反激转换器和正激转换器拓扑。