Flicker noise degeneration technique for VCO
US7486154B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 2006 |
| Grant date | Feb 3, 2009 |
| Priority date | — |
| Expiry date | Feb 12, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B5/1243
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An oscillating circuit having improved noise degeneration includes an oscillator and a noise degeneration circuit. The oscillator is adapted to provide a differential oscillating signal between first and second output terminals, and includes first and second transistors in communication with the first and second output terminals. The noise degeneration circuit includes cross-coupled capacitors and cross-coupled third and fourth transistors operated in a linear region. The noise degeneration circuit reduces the low frequency gm of the first and second transistors to lower the effect of flicker noise. At relatively high frequencies, the capacitors provide a virtual AC ground to the source terminals of the first and second transistors. The noise degeneration circuit receives a voltage signal from a biasing circuit adapted to track variations in electrical characteristics of the third and fourth transistors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.