Frequency generator and communication system using the same
US7177612B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 2004 |
| Grant date | Feb 13, 2007 |
| Priority date | — |
| Expiry date | Jul 21, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2203/45264
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A frequency generator which can perform stable frequency oscillation unaffected by temperature variation.A frequency generator having a differential amplifier (1) having an LC resonance circuit (10) as a load and buffer circuits (21, 22) feeding back an output of the differential amplifier to its input, wherein a temperature coefficient converter (5) converting an output voltage of a reference voltage generator (4) and its temperature dependence to a voltage having a predetermined voltage and temperature coefficient and outputting it is provided to control bias currents IEF of emitter follower circuits to be in proportion to temperature variation. There are a characteristic in which delay time of the emitter follower circuits constructing the buffer circuits is in inverse proportion to a transconductance of transistors and a characteristic in which the transconductance is in inverse proportion to temperature and is in proportion to the bias currents IEF. An oscillation frequency stable to temperature variation can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.