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. 18, 2005
Filed:
Feb. 21, 2003
Gilles P. Denoyer, San Jose, CA (US);
Dan Case, Gilroy, CA (US);
Gilles P. Denoyer, San Jose, CA (US);
Dan Case, Gilroy, CA (US);
Finisar Corporation, Sunnyvale, CA (US);
Abstract
A wide dynamic range transimpedance amplifier for fiber optics receivers. An automatic transimpedance gain control and DC cancellation control feedback circuit include a pnp transistor that is connected with the input signal. The impedance seen at the emitter of the pnp transistor changes according to the average value of the photodiode input current. Thus, large signal amplitudes are attenuated at the input of the transimpedance amplifier by the transistor and small signal amplitudes are amplified. The transistor is a variable impedance that can increase the optical overload without diminishing or reducing the optical sensitivity of the transimpedance amplifier.