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:
Jan. 31, 1989
Filed:
Jul. 28, 1987
Applicant:
Inventors:
Assignee:
Matsushita Electric Works, Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
307311 ; 307570 ; 250551 ;
Abstract
A semiconductor switching circuit comprises an output FET receiving a photovoltaic output generated by a diode array responsive to a light signal from a light emitting element, a depression mode driving FET connected at the drain and source to the gate and source of the output FET, and a constant voltage conduction element connected in parallel with a resistor connected across the gate and source of the driving FET. The sensitivity of the circuit is elevated by setting the value of this resistor relatively high, whereas high speed operation can be assured by having discharge current of an accumulated charge across the drain and gate of the output FET bypassed through the resistor.