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:
Sep. 09, 2003
Filed:
Oct. 29, 2002
Hongming An, San Diego, CA (US);
Brian Lee Abernethy, Escondido, CA (US);
Bruce Harrison Coy, San Diego, CA (US);
Applied MicroCircuits Corporation, San Diego, CA (US);
Abstract
A system and method are provided for reducing the threshold bias offset voltage in a comparator, by canceling and bypassing the bias offset current errors. The comparator system comprises amplification stages with bias cancellation circuitry and a threshold setting circuit. The bias offset current cancellation circuit is used to cancel the base current of differential amplifier input emitter follower. The bias offset current cancellation circuit also cancels the loading effect of amplifier input emitter-follower driving stage. The threshold offset voltage is further reduced by the threshold setting circuit. The threshold-setting circuit includes two integrators and a unit gain operation amplifier. The integrators have the input accept a single-ended input signal, an output connected to the negative input of the comparator, and an output connected to the unit gain operational amplifier, whose output is connected to the negative input of the comparator.