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:
May. 02, 2000
Filed:
Dec. 29, 1997
Kozo Sakamoto, Takasaki, JP;
Isao Yoshida, Nishitama-gun, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
There is disclosed a semiconductor apparatus such as a power MOSFET, an IGBT, or the like having therein a control circuit such as an over-heating protection circuit and an over-current protection circuit, which realizes both of high-speed operation and prevention of erroneous operation caused by a parasitic device. In order to prevent erroneous operation of a power MOSFET 30 and a protection circuit 21 caused by a parasitic npn transistor 29 of an MOSFET 32, a control circuit 20 controls so that when the voltage of a gate terminal 2 is positive relative to that of a source terminal 3, a switch circuit SW3 is turned on, when the voltage of the gate terminal 2 is negative relative to that of the source terminal 3, a switch circuit SW2 is turned on, and when the gate terminal 2 and the source terminal 3 have an almost same potential and a drain terminal 1 has a high potential, the switch circuit SW2 is turned on. By adding such a control circuit, an insulated gate semiconductor apparatus having therein the protection circuit according to the invention can reduce a leakage current flowing from the drain terminal to the gate terminal when a negative voltage is applied to the gate and can operate at high speed without causing drop of a drain breakdown voltage.