US 12,224,671 B2
Power supply circuit with two power conversion circuits
Kazuaki Mino, Kyoto (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Kyoto (JP)
Filed on Dec. 21, 2022, as Appl. No. 18/069,527.
Application 18/069,527 is a continuation of application No. PCT/JP2021/024307, filed on Jun. 28, 2021.
Claims priority of application No. 2020-115408 (JP), filed on Jul. 3, 2020.
Prior Publication US 2023/0124775 A1, Apr. 20, 2023
Int. Cl. H02M 3/335 (2006.01); H02M 1/00 (2006.01); H02M 1/08 (2006.01); H02M 1/32 (2007.01); H02M 1/42 (2007.01); H02M 7/217 (2006.01); H02M 7/537 (2006.01)
CPC H02M 3/33569 (2013.01) [H02M 1/007 (2021.05); H02M 1/008 (2021.05); H02M 1/08 (2013.01); H02M 1/32 (2013.01); H02M 1/4283 (2021.05); H02M 3/33507 (2013.01); H02M 7/217 (2013.01); H02M 7/537 (2013.01); H02M 1/0009 (2021.05)] 20 Claims
OG exemplary drawing
 
1. A power supply circuit comprising:
a transformer comprising a primary winding and a secondary winding;
a first power conversion circuit configured to convert a DC voltage into an AC voltage and output the AC voltage to the primary winding;
a rectifying and smoothing circuit configured to rectify and smooth an AC voltage output from the secondary winding;
a second power conversion circuit configured to boost a DC voltage output from the rectifying and smoothing circuit and supply to, a first load, a DC voltage lower than a rated voltage of the first load set in advance; and
a controller configured to:
determine whether an input voltage of the second power conversion circuit falls within a first reference voltage range set in advance, and
control the first power conversion circuit,
wherein, when the controller is configured to determine that the input voltage of the second power conversion circuit is greater than or equal to an upper limit of the first reference voltage range, the controller is configured to control the first power conversion circuit so as to reduce an output voltage of the second power conversion circuit, and
when the controller is configured to determine that the input voltage of the second power conversion circuit is greater than or equal to the upper limit of the first reference voltage range after the control of the first power conversion circuit, the controller is configured to stop the first power conversion circuit.