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:
Jul. 03, 2018
Filed:
Nov. 06, 2014
Meidensha Corporation, Tokyo, JP;
Hiromi Sako, Numazu, JP;
MEIDENSHA CORPORATION, Tokyo, JP;
Abstract
Upon turn-off of IGBT, by suppressing variations in collector-emitter voltage between IGBTs connected in series, risk of breaking IGBT due to overvoltage breakdown can be reduced. In protection circuit provided for each of the plurality of IGBTsconnected in series, between collector and emitter of IGBT, avalanche elements D˜D, resistance Rand avalanche element Dare sequentially connected in series. Capacitor Cand resistance Rare connected parallel between both ends of the avalanche element D, and capacitor Cand resistance Rare connected parallel between both ends of the avalanche element D. Between a common connection point of the resistance Rand the avalanche element Dand gate of the IGBT, resistance R, a parallel circuit of capacitor Cand resistance R, and a series component of Zener diodes ZDand ZDwhose polarities are opposite to each other, are connected in series.