Stable voltage reference circuit
US6215353A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 24, 1999 |
| Grant date | Apr 10, 2001 |
| Priority date | — |
| Expiry date | May 24, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05F3/30
- WIPO fieldControl
- WIPO sectorInstruments
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 (V1) that has a positive temperature dependence (dV1/dT) and a second AC input voltage (V2) that has a negative temperature dependence (dV2/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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.