Digitally adjustable crystal oscillator with a monolithic integrated oscillator circuit
US5805029A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1997 |
| Grant date | Sep 8, 1998 |
| Priority date | — |
| Expiry date | May 22, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B2201/0266
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The invention relates to a digitally adjustable crystal oscillator having a quartz crystal and a monolithic integrated oscillator circuit including a series combination of a first frequency-adjusting capacitor C1 and a second frequency-adjusting capacitor C2 connected in parallel with the quartz crystal and comprising parallel-connected first capacitance stages and parallel-connected second capacitance stages, respectively, and an inverter circuit connected in parallel with the quartz crystal and comprising a feedback resistor R.sub.K, the output of the innverter circuit being connected to a load resistor. The inverter circuit comprises parallel-connected inverter stages, and switching elements are provided within the inverter stages and cqapacitor stages in such a way that a respective one of the inverter stages as well as a first capacitance stage C.sub.1i and a second capacitance stage C.sub.2i are switchable into or out of circuit by means of a control signal I.sub.i.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.