US 12,267,010 B2
Switching power circuit
Toshimasa Namekawa, Ota Tokyo (JP); Ryoma Matsuo, Kawasaki Kanagawa (JP); and Katsumasa Tanaka, Nagareyama Chiba (JP)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (JP); and Toshiba Electronic Devices & Storage Corporation, Tokyo (JP)
Filed by Kabushiki Kaisha Toshiba, Tokyo (JP); and Toshiba Electronic Devices & Storage Corporation, Tokyo (JP)
Filed on Jan. 19, 2023, as Appl. No. 18/099,172.
Application 18/099,172 is a division of application No. 16/806,269, filed on Mar. 2, 2020, granted, now 11,594,963.
Claims priority of application No. 2019-161370 (JP), filed on Sep. 4, 2019.
Prior Publication US 2023/0155501 A1, May 18, 2023
Int. Cl. H02M 3/157 (2006.01); H02M 1/32 (2007.01); H02M 3/158 (2006.01)
CPC H02M 3/157 (2013.01) [H02M 1/32 (2013.01); H02M 3/158 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A switching power circuit, comprising:
a first switching transistor in which a main current path is connected between an input terminal to which a direct-current input voltage is applied and an output terminal supplying an output voltage;
an inductor that is connected between the switching transistor and the output terminal;
a first PWM signal generation circuit that generates a first PWM signal of which a duty ratio is changed in accordance with a first control voltage based on a control voltage output from a differential amplifier circuit comparing a reference voltage with a feedback voltage of the output voltage;
a first rectification diode that is connected in a forward direction towards the first switching transistor from a ground;
a second rectification diode that is connected in the forward direction towards the output terminal from the inductor;
a second switching transistor that is connected between an anode of the second rectification diode and the ground;
a second PWM signal generation circuit that generates a second PWM signal of which a duty ratio is changed in accordance with a second control voltage based on the control voltage, and which is applied to a gate of the second switching transistor; and
an overcurrent protection circuit that decreases a voltage of the reference voltage in a case where an output current of the first switching transistor is greater than a set current.