| CPC H02M 3/07 (2013.01) [H02M 1/0009 (2021.05); H02M 1/08 (2013.01)] | 17 Claims |
|
1. A switched capacitor voltage converter circuit configured to convert a first voltage into a second voltage, the switched capacitor voltage converter circuit comprising:
a switched capacitor converter, coupled between the first voltage and the second voltage; and
a control circuit, configured to control the switched capacitor converter to operate in a conversion mode having a voltage conversion ratio, and configured to generate control signals according to the conversion mode to control the switched capacitor converter to convert the first voltage into the second voltage;
wherein the switched capacitor converter comprises:
at least two capacitors;
a plurality of switches, coupled with the at least two capacitors; and
at least one inductor;
wherein the control signals comprise a charge operating signal and at least one discharge operating signal to control the plurality of switches to convert the first voltage into the second voltage;
wherein during a charge process of the conversion mode, the charge operating signal controls the plurality of switches, so that at least one of the at least two capacitors and the at least one inductor are connected in series between the first voltage and the second voltage to form a charging path and operate in a resonant operation mode;
wherein during at least one discharge process of the conversion mode, the at least one discharge operating signal controls the plurality of switches, so that the at least two capacitors and the at least one inductor are connected in series between the second voltage and a direct-current (DC) potential, to simultaneously or alternately form a plurality of discharging paths and operate in the resonant operation mode;
wherein in the conversion mode, the charge process and the at least one discharge process are performed repeatedly and alternately, so as to convert the first voltage into the second voltage;
wherein in the conversion mode, the charge operating signal and the at least one discharge operating signal have respective conduction periods which do not overlap with each other, so that the charge process and the at least one discharge process do not overlap with each other;
wherein during a mode switching period wherein the control circuit is switched from a present conversion mode to a next conversion mode, the control signals are changed to a mode switching control signal, which comprises a mode-switching charge signal, at least one mode-switching discharge signal, and a unidirectional conduction signal;
wherein the unidirectional conduction signal is configured to control at least two forward switches of the plurality of switches to operate in a unidirectional conduction mode, wherein during the unidirectional conduction mode, each of the at least two forward switches provides a current channel unidirectionally toward the second voltage;
wherein the mode-switching charge signal and the at least one mode-switching discharge signal control the switches other than the at least two forward switches operating in the unidirectional conduction mode, so as to convert the first voltage into the second voltage;
wherein the control circuit comprises:
a duty cycle determination circuit, configured to compare a ramp-up voltage of a ramp-up node with a periodic waveform signal to generate a duty cycle signal;
a duty cycle distribution circuit, configured to generate the mode-switching charge signal and the at least one mode-switching discharge signal according to the duty cycle signal; and
a ramp-up voltage generating circuit, coupled to the duty cycle determination circuit, and configured to generate the ramp-up voltage of the ramp-up node during the mode switching period; and
wherein the ramp-up voltage of the ramp-up node gradually increases during the mode switching period, so that the duty cycle of the mode-switching charge signal and the at least one mode-switching discharge signal gradually increases correspondingly.
|