Abstract: Communicating a power control feedback signal from a system is disclosed. In some embodiments, upon determining how to control input power which may be based at least in part, for example, on an in situ measurement of an operating condition in an operating environment, an appropriate symbol is constructed based upon the determination and is transmitted on a single line. In some embodiments, the single line corresponds to the reference voltage of an associated power supply.

Abstract: 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.