Patent ID: 8095813

Claim:
An integrated circuit system containing a clock generation apparatus coupled to second circuitry, the second circuitry having an input terminal and an output terminal, the clock generation apparatus comprising: a clock generator adapted to provide a clock signal on a first terminal coupled to the input terminal; a sensor coupled by a second terminal to the output terminal of the second circuitry, the sensor adapted to detect a power conservation mode and a power resumption mode of the second circuitry in response to a first signal and a second periodic signal generated by the second circuitry that identify the power conservation mode and the power resumption mode, respectively; and a processor coupled to the sensor and to the clock generator, the processor configured to reduce power to the clock generator in response to detection of the power conservation mode by the sensor, and to increase power to the clock generator in response to detection of the power resumption mode by the sensor, said processor further configured to control the clock generator to convert the clock signal provided on the first terminal to a fixed voltage in response to detection of the power conservation mode by the sensor and convert the fixed voltage to the clock signal in response to detection of the power resumption mode by the sensor.