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:
Nov. 01, 2005
Filed:
Aug. 24, 2004
Makoto Sakaguchi, Shiga, JP;
Makoto Sakaguchi, Shiga, JP;
NEC Compound Semiconductor Devices, Ltd., Kanagawa, JP;
Abstract
A photoelectric current and voltage converting circuit converts a photo current Ipd generated by the input to photo diode into a voltage Va by a feedback resistor connected to an inverting input and an output of an amplifier, and compares the output voltage Va with a threshold voltage Vth from a reference voltage circuit to output a binary signal. Divided voltage Vb gained from a connecting node of the feedback resistors is inputted to a non-inverting input of the reference voltage circuit and is offset to a higher voltage by Vos to generate a threshold voltage Vth. As a result, the threshold voltage Vth can be supplied which impedance is low and robust to noise, and errors of the comparator or jitter of the output of the comparator are suppressed.