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:
Jul. 02, 1996
Filed:
Sep. 22, 1995
Henri P Dautet, Quebec, CA;
Joseph D DesChamps, Quebec, CA;
EG&G Limited, Vaudreail, Quebec, CA;
Abstract
An active quench circuit for interrupting the current flow in an avalanche photodiode (APD) operating in Geiger mode and for resetting the APD. The invention increases the speed of quenching and reduces the time required to bring the APD voltage back to its operating voltage above the breakdown voltage. The circuit includes a small inductor which isolates the reset circuit from the APD during the initial discharge and which provides a current pulse into the APD immediately after the end of the quenching operation to recharge the diode. The reset circuit also includes a diode assembly that increases the speed of the avalanche current pulse and that prevents the circuit from oscillating or latching under certain operating conditions. The circuit presents a low impedance to the APD during during reset, and is much less sensitive to the APD capacitance than prior art circuits.