The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 23, 2022
Filed:
Dec. 06, 2019
Fremont Micro Devices Corporation, Guangdong, CN;
FREMONT MICRO DEVICES CORPORATION, Shenzhen, CN;
Abstract
Disclosed are a Darlington transistor drive circuit, a Darlington transistor drive method implemented based on such Darlington transistor drive circuit, and a constant current switching power supply including such Darlington transistor drive circuit. The Darlington transistor drive circuit includes a drive current circuit, two switch units, and a drive control circuit used for controlling the two switch units to be switched off during the switching-on cycle of the Darlington transistor and to be switched on during a switching-off cycle of the Darlington transistor, and for changing an equivalent resistance of the two switch units at different stages during the switching- off cycle of the Darlington transistor. The switching-off time delay of the Darlington transistor is greatly reduced while achieving the EMI optimization. In additional, the switch loss of Darlington transistor is small when it is switched off, and the efficiency is improved.