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:
Apr. 30, 1991
Filed:
Mar. 19, 1990
Frederick G Weiss, Newberg, OR (US);
Daniel G Knierim, Beaverton, OR (US);
TriQuint Semiconductor, Inc., Beaverton, OR (US);
Abstract
An electrical circuit (30) corrects for the presence of noise current and current drift in the currents developed by each current source transistor Q.sub.0, Q.sub.1, Q.sub.2, Q.sub.3, . . . Q.sub.n in a current source array. The electrical circuit corrects for the presence of noise current and current drift by simultaneously inducing in each current source correction currents whose values sum to cancel the current drift and noise. A noise suppression circuit includes an amplifier having an open loop gain, A.sub.v, which is configured to adjust the magnitudes of the multiple currents in response to the introduction of a noise current, i.sub..delta., in any one of the currents. The adjustment substantially cancels i.sub..delta. and thereby substantially reduces the presence of i.sub..delta. in the output current. The presence of i.sub..delta. in the output signal is substantially equal to i.sub..delta. /(1+A.sub.v).