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, 2006
Filed:
Feb. 26, 2004
Koji Nakamura, Toyohashi, JP;
Manabu Nomura, Toyota, JP;
Satoshi Yoshimura, Kariya, JP;
Denso Corporation, Kariya, JP;
Abstract
A temperature sensor () detects the temperature of a MOS transistor (), and a current detecting circuit () detects current flowing in the MOS transistor (). When the voltage corresponding to the detected temperature or the voltage corresponding to the detected current is increased to a threshold value or more, an overheat state detecting signal and further switching signal is set to a high level. As a result, a switch circuit in a driving circuit () is turned on, and the gate resistance value becomes the parallel value of a resistor (), and the PWM frequency in the PWM control circuit is lowered, whereby the switching loss of the MOS transistor () can be reduced under the state that the motor () is rotated.