US 12,267,018 B2
Power supply circuit and charging device
Senlong Jiang, Dongguan (CN); Chih-wei Chiu, Dongguan (CN); Jialiang Zhang, Dongguan (CN); Chen Tian, Dongguan (CN); and Jun Zhang, Dongguan (CN)
Assigned to GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD., (CN)
Filed by GUANGDONG OPPO MOBILE TELECOMMUNICATIONS CORP., LTD., Dongguan (CN)
Filed on Sep. 9, 2022, as Appl. No. 17/941,689.
Application 17/941,689 is a continuation of application No. PCT/CN2021/078536, filed on Mar. 1, 2021.
Claims priority of application No. 202010172177.5 (CN), filed on Mar. 12, 2020.
Prior Publication US 2023/0006557 A1, Jan. 5, 2023
Int. Cl. H02M 3/335 (2006.01); H02M 1/08 (2006.01); H02M 7/219 (2006.01); H03K 3/57 (2006.01)
CPC H02M 3/335 (2013.01) [H02M 1/08 (2013.01); H02M 7/219 (2013.01); H03K 3/57 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A power supply circuit, comprising:
a transformer circuit comprising a pulse transformer and a switch control circuit; wherein a primary winding of the pulse transformer is connected to a power supply and the switch control circuit, and the switch control circuit is configured to modulate a voltage on the primary winding into a pulse voltage; and
a first power supply conversion circuit, wherein an input terminal of the first power supply conversion circuit is connected to a secondary winding of the pulse transformer to convert a voltage on the secondary winding of the pulse transformer to be within a first preset voltage range and then to be output in the case of a voltage output by the secondary winding being out of the first preset voltage range, and an upper limit value of the first preset voltage range is less than a maximum value of an output voltage of the transformer circuit.