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:
Feb. 21, 1978
Filed:
Oct. 12, 1976
Applicant:
Inventor:
Thomas P Redfern, San Jose, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H03K / ; H01L / ; H01L / ; H03K / ;
U.S. Cl.
CPC ...
307251 ; 307240 ; 307355 ; 357 23 ; 357 41 ;
Abstract
A chopper stabilized comparator which compares two low level DC signals, and converts these signals to an AC signal which is amplified by AC amplifiers. The AC amplifier output is proportional to the difference between the two DC signals. The circuit has the advantage that it does not have any DC offset terms, for example, it does not drift with temperature. The comparator is implemented in CMOS technology wherein the actual physical layout of the circuit is chosen such that changes in mask orientation during the fabrication process have no effect upon the proper operation of the circuit.