Stimulated quick start oscillator
US6819195B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 2003 |
| Grant date | Nov 16, 2004 |
| Priority date | — |
| Expiry date | Jun 25, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K3/0307
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An oscillation circuit including a resonating element such as a crystal, an inverting amplifier and a resistor that each span the resonating element terminals, and two capacitors that capacitively couple the resonating element terminals to ground. An AC current source such as a temperature compensated and properly trimmed ring oscillator generates a differential AC current when active. The differential AC current has a frequency that is within a tolerance of the resonant frequency of the resonant element for a given set of operating conditions. Two buffers connect the differential outputs of the AC current source to respective terminals of the resonating element to thereby shorten startup time. A control logic circuit carefully times the application of the differential AC current to the resonating element terminals such that the current is applied for a sufficient time such that startup would occur under any anticipated operating condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.