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:
May. 10, 2011
Filed:
Mar. 03, 2008
Weilong William Lee, West Covina, CA (US);
Joseph C. Chon, Fremont, CA (US);
Chiahung Chiu, Taipei, TW;
Wayne Liao, Taipei, TW;
Weilong William Lee, West Covina, CA (US);
Joseph C. Chon, Fremont, CA (US);
Chiahung Chiu, Taipei, TW;
Wayne Liao, Taipei, TW;
Wavesplitter Technologies, Inc., Fremont, CA (US);
Abstract
A method and apparatus is provided for biasing an avalanche photodiodes (APD). The method includes developing a first output signal s(v) from the APD when biased with a first bias voltage vand developing a second output signal s(v) from the APD when biased with a second bias voltage v, wherein s(v)=PRZM(v), (P) is an light power illuminating the APD, R is a responsivity of the APD, M(v) is an APD avalanche gain and Z is a trans-impedance amplifier gain (Z). The method continues by acquiring a ratio r=s(v)/s(v)=PRZM(v)/[PRZM(v)]=M(v)/M(v) and invoking a feedback control method to bias the APD using the ratio r.