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. 02, 1999
Filed:
Aug. 08, 1997
Vittorio Comino, Keansburg, NJ (US);
Dima David Shulman, Marlboro, NJ (US);
Susan Jeanne Walker, Howell, NJ (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
A circuit for compensating for the input offset voltage of a logarithmic amplifier includes a digital comparator, a logic circuit, and a digital-to-analog converter (DAC) in a feedback loop. The comparator is connected to the output of the log amplifier and digitally indicates the polarity of the input offset voltage when the amplifier input is set to zero. The logic circuit uses the digital output of the comparator to form an adjustable digital compensation signal. This digital compensation signal is applied to the DAC to generate an analog compensation signal that is injected into the input of the logarithmic amplifier to cancel the input offset voltage. The process is repeated until the proper or best compensation signal is produced.