Synchronous rectification circuit, wireless charging system and synchronous rectification method

Abstract

The invention relates to a synchronous rectification circuit, a wireless charging system and a synchronous rectification method. The synchronous rectification circuit comprises: a zero-crossing comparator, used for processing a signal obtained from a coil to obtain a first alternating-current signal and a second alternating-current signal; an FPGA module, used for obtaining dead zone protection time according to the first alternating-current signal and the second alternating-current signal; an MOS transistor driving module, used for forming a driving signal of an MOS transistor rectification module according to the dead zone protection time obtained by the FPGA module; and the MOS transistor rectification module, used for realizing synchronous rectification according to the driving signal and outputting a signal after synchronous rectification to a load. With the adoption of the synchronous rectification circuit, the wireless charging system and the synchronous rectification method, on the basis of ensuring synchronous rectification efficiency, the requirement of real-time control on a time sequence in synchronous rectification is lowered, the corresponding dead zone time can be set by adaptively following alternating-current signals of different frequencies, and the design cost of synchronous rectification control is reduced.

Description

Technical field [0001] The present invention relates to the field of electronic technology, in particular to wireless charging, and specifically refers to a synchronous rectification circuit, a wireless charging system and a synchronous rectification method. Background technique [0002] Compared with diode rectification, synchronous rectification technology can reduce the loss of the rectifier circuit itself and improve the efficiency of the whole machine. At present, synchronous rectification technology is often used in circuit applications that require high efficiency. In order to avoid simultaneous conduction of MOS switch tubes with alternate conduction, the synchronous rectification control sequence is more complicated, so that the complexity and stability of the circuit structure are sacrificed in exchange for efficiency. [0003] The existing synchronous rectification technology is mainly based on accurately sampling the PWM wave timing of the primary side switch tube. Bef...

AI Technical Summary

Problems solved by technology

In addition, when the sampled AC signal is disturbed, error waveforms such as glitches will appear in the zero-crossing detection

Images