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:
Aug. 23, 2011
Filed:
Feb. 11, 2009
Takashi Imura, Chiba, JP;
Takao Nakashimo, Chiba, JP;
Takashi Imura, Chiba, JP;
Takao Nakashimo, Chiba, JP;
Seiko Instruments Inc., , JP;
Abstract
A voltage regulator has a first error amplifier circuit that amplifies a difference between a first reference voltage and a voltage based on an output voltage of an output transistor, and an overcurrent protection circuit that detects an overcurrent flowing through the output transistor and limits a current of the output transistor. The overcurrent protection circuit has an output current detection transistor that feeds a detection current in accordance with an output current of the output transistor, a voltage generation circuit that generates a voltage based on the detection current, a second error amplifier circuit that amplifies a difference between the voltage from the voltage generation circuit and a voltage set by a second reference voltage supplied by a temperature detection circuit and a voltage based on the output voltage, and an output current limiting transistor that controls a gate voltage of the output transistor and has a gate that is controlled by an output of the second error amplifier circuit.