Ultra low power apparatus and method to wake up a main processor

摘要

An apparatus and method for waking up a main processor (MP) in a low power or ultra-low power device preferably includes the MP, and a sub-processor (SP) that utilizes less power than the MP to monitor ambient conditions than the MP, and may be internalized in the MP. The MP and SP can remain in a sleep mode while an interrupt sensor monitors for changes in the ambient environment. A sensor is preferably an interrupt-type sensor, as opposed to polling-type sensors conventionally used to detect ambient changes. The MP and SP may remain in sleep mode, as a low-power or an ultra-low power interrupt sensor operates with the SP being in sleep mode, and awakens the SP via an interrupt indicating a detected change. The SP then wakes the MP after comparing data from the interrupt sensor with values in storage or with another sensor.

主权项

1. A method of waking up a main processor in an ultra-low power electronic device, the method comprising:
monitoring for a predetermined condition by an interrupt sensor when a sub-processor that controls the interrupt sensor is in a sleep mode; sending by the interrupt sensor an interrupt signal to the sub-processor upon sensing a change in the predetermined condition being monitored, said sub-processor being configured to wake up from sleep mode upon receiving the interrupt signal and evaluate data received from the interrupt sensor; wherein when the sub-processor determines that the data received from the interrupt sensor has reached a predetermined threshold value or is within a predetermined range of validity, the sub-processor sending a signal to wake up a main processor that is coupled to the sub-processor, wherein the predetermined condition being monitored comprises an ambient environment of the electronic device, and wherein the interrupt sensor comprises an infrared (IR) gesture sensor that senses a hand wave gesture as a change in the ambient environment and returns the electronic device to an active status.