High accuracy RC oscillator
US8497741B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 2011 |
| Grant date | Jul 30, 2013 |
| Priority date | — |
| Expiry date | Oct 12, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/02315
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A device includes an RC oscillator circuit and incorporates various features that individually and in combination can help improve the stability or accuracy of the oscillator output frequency. The oscillator circuit is operable to provide a tunable output frequency and includes a bias circuit switchable between first and second modes of operation. One of the modes has less drift in oscillator bias current relative to the other mode. The device also includes drift compensation circuitry that is operable to compensate for drift in the oscillator output frequency in a closed-loop mode of operation based on a comparison of the oscillator output frequency with a reference frequency. The device further includes a processor operable to compensate for temperature-based drift in the oscillator frequency in an open-loop mode of operation based on a measured temperature value in the vicinity of the oscillator circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.