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:
Jun. 11, 2002
Filed:
Oct. 19, 2000
Kazunori Oyabe, Nagano, JP;
Fuji Electric Co., Ltd., Kawasaki, US;
Abstract
When an alarm signal provided by an inverter forming an I/F provided for the circuit on the high side enters an active (L) state, the output of the inverter indicates an H state. Then, the N-channel MOS type FET enters an ON state. At this time, the N-channel MOS type FET is connected to the I/F on the low side using a diode. Therefore, when the diode enters a normal bias state, that is, when the reference potential of the above mentioned two I/Fs approach each other, an electric current flows from the power supply to the N-channel MOS type FET through a resistor. As a result, by a voltage drop, a voltage arises in the resistor, and the output of the inverter indicates the H state. Since the output of the inverter is connected to a control unit, the control unit performs a process according to an alarm signal. Thus, the electric power conversion apparatus having a circuit on a low side for performing a switching operation based on reference potential and a circuit on a high side for performing a switching operation based on floating reference potential which is different from the reference potential by a variable amount can be smaller and less costly.