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:
Jun. 24, 2003
Filed:
May. 25, 2001
Thomas Blon, Santa Cruz, CA (US);
Sasan Cyrusian, Scotts Valley, CA (US);
Infineon Technologies AG, Munich, DE;
Abstract
An active offset cancellation circuit for an open loop differential amplifier is disclosed. The amplifier is operated on a two-phase clock where the normal operation occurs on the first phase and offset detection and cancellation occurs on the second phase. On the second phase, the offset cancellation circuit measures the offset created by the amplifier when both differential inputs are connected to a common source. The circuit then adjusts a bias current and stores this adjustment to cancel offset during the operational phase of the amplifier. During the operational phase, the first phase of the clock, the stored adjustment is used to bias the current in one of the two input stages of the amplifier, canceling any offset imparted by the amplifier circuitry. One each clock cycle, any additional offset is similarly detected and canceled.