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:
Oct. 29, 1991
Filed:
Jun. 19, 1989
Charles L Vinn, Milpitas, CA (US);
Para K Segaram, Campbell, CA (US);
Raytheon Company, Lexington, MA (US);
Abstract
A precision amplifier that, in response to digital inputs, zeros its offset voltage. The precision amplifier comprises a traditional amplifier; a current source controlled by a counter; a comparator; test switches; and control logic. A digital input, such as might be generated from a microprocessor, initiates the offset adjustment. The test switches disconnect the amplifier inputs from external package connections and connect the inputs together. The counter begins to count, changing the current produced by the current source at each count. The current from the current source is applied to the offset adjust circuit of the amplifier which changes the offset voltage as the current changes. The counter counts until the comparator indicates the offset voltage has been zeroed. Alternative embodiments allow the precision amplifier to adjust for offset introduced by circuitry connected to the input and the output of the precision amplifier.