Watch circuit with oscillator gain control
US4387350A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1980 |
| Grant date | Jun 7, 1983 |
| Priority date | — |
| Expiry date | Dec 24, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04G19/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A watch circuit arrangement for conserving battery power includes a feedback connection between the crystal oscillator of the watch circuit and the display voltage generator which is responsive to the crystal oscillator output to develop sufficient output voltage for the watch display. Specifically, the output of the display voltage generator, which may be a voltage multiplier, is sensed by a display voltage sensing circuit which controls the gain of the crystal oscillator. Initially, when battery power is applied to the watch circuit, the voltage multiplier has zero output voltage, which conditions the crystal oscillator to have a sufficiently high gain to start the oscillator. After several cycles of oscillator signal, the voltage multiplier output increases, which conditions the crystal oscillator to have a lower gain for reducing power consumption while sustaining oscillation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.