Crystal-less oscillator circuit with trimmable analog current control for increased stability
US6798299B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 2001 |
| Grant date | Sep 28, 2004 |
| Priority date | — |
| Expiry date | Sep 19, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L2207/10
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A crystal-less oscillator circuit with trimmable current control. In one embodiment, the present invention provides an oscillator circuit comprising a digital to analog converter circuit for generating a current, a band gap reference circuit for generating a voltage, and a relaxation oscillator circuit for creating a frequency based on the current and the voltage. In one embodiment, the digital to analog converter circuit comprises a trimmable current control. In one embodiment, the relaxation oscillator circuit is coupled to a frequency doubler circuit wherein the frequency is passed through the frequency doubler circuit for generating a second frequency. In another embodiment, the present invention provides a phase locked loop circuit comprising a phase detector circuit and the aforementioned oscillator circuit. In another embodiment, the present invention provides a microcontroller comprising a phase locked loop circuit comprising a phase detector circuit and the aforementioned oscillator circuit. The present invention provides an oscillator with stable frequency without the use of a crystal oscillator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.