Integrated circuit frequency generator

摘要

An integrated circuit frequency generator is disclosed. In some embodiments, the frequency generator comprises an electronic oscillator configured to generate an oscillator frequency and calibration circuitry configured to periodically calibrate the electronic oscillator with respect to a reference frequency source. When a primary power source is unavailable, an output frequency is generated from the oscillator frequency, and the reference frequency source is powered-on only during calibration cycles.

主权项

1. A system, comprising:
a crystal configured to generate an output frequency when a main power source is available; and an oscillator configured to generate the output frequency when the main power source is not available, wherein the oscillator is calibrated at prescribed calibration intervals to track the accuracy of the crystal and wherein the crystal is powered-on during calibration intervals to calibrate the oscillator and otherwise powered-off when the main power source is not available.