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, 1996
Filed:
Dec. 29, 1993
Krishnaswamy Nagaraj, Wescosville, PA (US);
AT&T Corp., Murray Hill, NJ (US);
Abstract
A bandgap voltage generator using a simple bandgap voltage reference supply circuit which has virtually no power supply rejection ratio (PSRR) which can produce an output bandgap voltage, V.sub.BG, using an extremely low power supply voltage, V.sub.DD. In order to increase the PSRR, a signal generated by the bandgap voltage reference supply circuit is amplified by a high gain amplifier circuit comprised of two cascode connected FETs. The highly amplified signal generated by the high gain amplifier circuit drives a voltage regulator, comprised of an FET used as a voltage controlled current sink, which regulates the voltage supplied from the power supply, V.sub.DD, to the bandgap voltage reference supply circuit. This combination of a bandgap voltage reference with virtually no PSRR and a high gain amplifier results in a bandgap voltage generator with a very high PSRR.