CMOS voltage controlled oscillator
US6011443A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 16, 1998 |
| Grant date | Jan 4, 2000 |
| Priority date | — |
| Expiry date | Jul 16, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/354
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A CMOS voltage controlled oscillator (VCO) having an improved voltage-to-current converter and an active MOS load operating in the triode region to provide improved performance characteristics including a small differential logic swing and a high frequency output. The voltage-to-current converter of the CMOS VCO comprises a pair of MOS transistors, one of which has an aspect ratio (W.sub.P /L.sub.P) and the other of which has an aspect ratio (W.sub.P /L.sub.P)/n, wherein 1<n<4. This configuration causes a third MOS transistor in the voltage-to-current converter to operate exclusively in the triode region. The CMOS VCO also includes an ICO portion having a plurality of delay stages connected in a ring configuration. Each of the delay stages comprises a pair of input MOS transistors and a pair of load MOS transistors. In accordance with the invention, the voltage-to-current converter causes each of the load MOS transistors to operate in the triode region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.