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:
Apr. 12, 2011
Filed:
Jul. 10, 2009
Hiroyasu Ishizuka, Ome, JP;
Kazuo Tanaka, Hachioji, JP;
Hiroyasu Ishizuka, Ome, JP;
Kazuo Tanaka, Hachioji, JP;
Renesas Electronics Corporation, Kawasaki-shi, JP;
Abstract
A protection circuit with suppressed erroneous operation due to power source fluctuation has a first resistor and a capacitor connected in series between a power source line and a ground line, an inverter with an input connected between the first resistor and the capacitor, and a MOS transistor with a gate electrode that receives an output of the inverter and with a drain electrode and source electrode connected to the power source line and the ground line. When high voltage fluctuation occurs in the power source line, a level change at a connection point between the first resistor and the capacitor is delayed according to a time constant. By the delay, the MOS transistor that receives an output of the inverter is temporarily turned on and discharges a high voltage to the ground line.