UNIVERSAL SERIAL BUS WAKEUP CIRCUIT

摘要

A circuit is attached in parallel to a universal serial bus interface of a data processing system. A capacitor in the circuit is charged by receiving power from a power pin of the universal serial bus interface while the data processing system is not in a reduced power state. A vibration sensor is unpowered while the data processing system is not in a reduced power state. The vibration sensor is disconnected from a data pin of the universal serial bus interface while the data processing system is not in a reduced power state. When the data processing system enters a reduced power state, the capacitor provides power to the vibration sensor. When a vibration is detected by the vibration sensor, a switch connects the vibration sensor to the data pin of the universal serial bus interface, providing a wake up signal to the data processing system.