US 12,074,508 B2
Microcontroller with slew-rate control circuit
Makoto Shinohara, Kawasaki Kanagawa (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 Aug. 22, 2022, as Appl. No. 17/893,010.
Claims priority of application No. 2022-036472 (JP), filed on Mar. 9, 2022.
Prior Publication US 2023/0291297 A1, Sep. 14, 2023
Int. Cl. H02M 1/00 (2007.01); H02M 1/088 (2006.01); H02M 1/36 (2007.01)
CPC H02M 1/0029 (2021.05) [H02M 1/088 (2013.01); H02M 1/36 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A microcontroller with a slew-rate control circuit, comprising:
a pre-drive circuit configured to charge and discharge a gate of at least one output power transistor with a constant current;
a measuring circuit configured to measure a transition time period during which a drain-to-source voltage of the at least one output power transistor connected to the pre-drive circuit makes a transition between a first voltage and a second voltage; and
a microprocessor configured to read the transition time period measured by the measuring circuit,
wherein the microprocessor
smooths a plurality of transition time periods read over a plurality of cycles, to calculate a smoothed transition time period, and
controls a constant current set value of the pre-drive circuit such that the constant current set value decreases when the smoothed transition time period is shorter than a predetermined time period and the constant current set value increases when the smoothed transition time period is longer than the predetermined time period.