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. 10, 2001
Filed:
May. 24, 1999
Lanny L. Lewyn, Laguna Beach, CA (US);
Pairgain Technologies, Inc., Tustin, CA (US);
Abstract
The invention provides a stable voltage reference circuit that has a single reference diode junction. Two separate current sources are switched so as to alternately apply a first and second current to the junction, with the second current being larger than the first. The voltage over the junction thereby alternates between a first AC input voltage (V,) that has a positive temperature dependence (dV,/dT) and a second AC input voltage (V,) that has a negative temperature dependence (dV,/dT). Combining circuitry is included for adding the first and second input voltages and for thereby generating an output voltage (Vref) substantially constant with absolute temperature. The combining circuitry preferably includes an amplifier that has, for the first input voltage, a gain substantially equal to the ratio of the negative temperature dependence divided by the positive temperature dependence. The amplifier is preferably implemented as an AC amplifier, with input and feedback elements that include a monolithic capacitor network.