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. 13, 2021
Filed:
Dec. 15, 2017
Facebook, Inc., Menlo Park, CA (US);
Shih-Cheng Wang, Cupertino, CA (US);
Facebook, Inc., Menlo Park, CA (US);
Abstract
In one embodiment, a method includes receiving, at an input of a transimpedance amplifier, an input electrical-current signal. The electrical-current signal includes a photodetector current and a DC cancellation current. The photodetector current corresponds to an input optical signal and includes an alternating-current (AC) portion and a direct-current (DC) portion. The method also includes performing, by the transimpedance amplifier, a transimpedance amplification of the input electrical-current signal to produce, at an output of the transimpedance amplifier, an output voltage signal corresponding to the input electrical-current signal. The method further includes providing, by a current-control circuit coupled to the input and the output of the transimpedance amplifier, the DC cancellation current to the input of the transimpedance amplifier, where the DC cancellation current is based on the output voltage signal.