Multi-phase switched capacitor power converter and control method thereof

Abstract

A multi-phase switched capacitor power converter and a control method thereof are disclosed. The multi-phase switched capacitor power converter includes a first phase converting circuit and a second phase converting circuit. The first phase converting circuit and the second phase converting circuit include switches and a flying capacitor respectively. The switches are coupled in series and there are a first node and a second node between the switches. The flying capacitor is coupled to the first node and the second node. When the first phase converting circuit is in an operating mode and the second phase converting circuit is in a standby mode, the control method controls a part of the switches in the second phase converting circuit continuously conducted to charge the flying capacitor. The multi-phase switched capacitor power converter can prevent surge current in the phase change moment and sustains a stable output voltage, thereby improving working performance of the multi-phase switched capacitor power converter.

Description

technical field [0001] The present invention is related to multi-phase power converters, in particular to a multi-phase switched capacitor power converter and its control method. Background technique [0002] Generally speaking, a multi-phase switched capacitor power converter includes at least a first phase conversion circuit and a second phase conversion circuit, and each phase conversion circuit includes a flying capacitor and a plurality of switches connected in series. [0003] Such as figure 1 As shown, before time T1, the multi-phase switched capacitor power converter is light-loaded, the phase control signal STEP is at a low level, the pulse width modulation signal PWM1 is enabled and the pulse width modulation signal PWM2 is disabled; at time T1, The multi-phase switched capacitor power converter changes from light load to heavy load, the phase control signal STEP also changes from low level to high level, the pulse width modulation signal PWM1 remains enabled, and...

AI Technical Summary

Problems solved by technology

[0004] However, in the commutation process, the multiphase switched capacitor power converter usually does not have a special mechanism to precharge the flying capacitor, so that the first switch coupled to the input voltage in the activated second phase conversion circuit will be in time Inrush current (Inrush current) IOUT2 ​​of T1 will burn out, or the output voltage VOUT will have peak fluctuations and become unstable, seriously affecting the performance of the multi-phase switched capacitor power converter, which needs to be improved urgently

Images