Fast startup crystal oscillator circuit with programmable injection time and adaptive startup time to achieve high amplitude oscillation
US11705861B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 29, 2022 |
| Grant date | Jul 18, 2023 |
| Priority date | — |
| Expiry date | Jun 29, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B2201/025
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A first three state driver injects a first clock signal into a crystal through an input node during a startup phase of a crystal oscillator and a second three state driver injects a second signal into the crystal through an output node during the startup phase. The first and second signals are anti-phase signals. The crystal oscillator circuit includes a first amplifier that is used during starting up and steady-state operation and includes a second amplifier. The injection through the input and output nodes is disabled after a fixed time. After injection ends, the second amplifier is turned on if voltage on the output node has reached a desired voltage and left off otherwise. If the second amplifier is turned on, the second amplifier is turned off when the voltage on the output node reaches the desired voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.