System, method and apparatus for controlling supply of backup power to first and second power planes in the event of a power failure of a main power supply

摘要

A circuit board includes a first circuit connected to a first power plane, a second circuit connected to a second power plane, and a power controller connected to the second power plane. The power controller connects the second power plane to a power subsystem such that the second circuit receives a main power signal through the second power plane while the power subsystem provides the main power signal to the first circuit through the first power plane. The power controller (i) detects a power failure event in which the power subsystem provides a backup power signal in place of the main power signal and, in response to the power failure event, (ii) disconnects the second power plane from the power subsystem such that the second circuit does not receive the backup power signal thus reducing backup power consumption.