Voltage-controlled oscillator
US5821823A · kind A · utility
12Cited by
1References
9Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 31, 1997 |
| Grant date | Oct 13, 1998 |
| Priority date | — |
| Expiry date | Jul 31, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/03
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A voltage-controlled oscillator (VCO) includes a plurality of differential amplifiers which are ring-connected. Each amplifier includes two FETs, the sources of which are coupled. The coupled sources of each amplifier are connected to series-connected FETs which is part of a current mirror circuit. The series-connected FETs decrease transconductance of (i.e., increase impedance against) fluctuations in a power supply voltage, so that fluctuations in current flowing in the amplifiers are lessened. Thus, power-supply rejection ratio of the VCO increases and fluctuations in the VCO frequency are lessened.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.