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:
Feb. 18, 2014
Filed:
Jan. 13, 2010
Daisuke Mashimo, Kawasaki, JP;
Hiroki Ikeda, Hachioji, JP;
Yoshinobu Morita, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a gain-switching-type transimpedance amplifier, in order to provide a technique capable of preventing unnecessary gain switching caused when noise is received, and preventing decrease in sensitivity caused when noise with a large input level is received, and then, a burst signal with a small input level is received, a transimpedance amplifierincludes: a pre-amplifierto which the burst signal is inputted; an average detection start determination unitfor comparing an output of a pre-amplifierwith a first threshold voltage; an average detection circuitfor detecting and outputting an average value of the output of the pre-amplifierduring a certain period of time from a time point when the output of the pre-amplifierexceeds the first threshold voltage; and a gain switching control unitfor determining whether to switch a gain of the pre-amplifierbased on an output of the average detection circuit