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:
Mar. 08, 2005
Filed:
Sep. 08, 2003
Lothar Schmidt, Rodenberg, DE;
Karlheinz Muth, Hannover, DE;
Martin Braier, Hannover, DE;
Texas Instruments Deutschland GmbH, Freising, DE;
Abstract
A transimpedance amplifier circuit comprising transistors, a constant current source, a load resistor, and the feedback resistor with a shunt circuitry consisting of the additional transistors, which are driven for example with electrically adjustable voltage sources. In a bipolar npn implementation the amplifier stage consists of a common emitter input transistor Q, a transistor Qwith its base connected to the collector of the first transistor operates as an emitter follower. A resistor RF connected between the emitter of said second transistor and the base of said first transistor provides a voltage controlled current feedback from the amplifier output to its input. The output voltage VOUT is generated at the emitter node of said second transistor. A shunt circuitry consists of a third and a fourth transistor Qand Qconnected in shunt across resistor RF. In an embodiment, the base node voltages of the transistors Qand Qare adjusted by control voltage sources. By means of an appropriate implementation of these voltage sources the maximum and minimum limits of the output voltage VOUT is defined, which can easily be implemented with arbitrary temperature or supply voltage dependency.