Control for electrically isolating power supply from external source with momentary switch and latching relay controlled by signal generated from power supply voltage

摘要

A system includes a power supply and a power switch to connect an external power source that is external to the system to the power supply. The power switch has an on position and an off position. The power switch if actuated to the off position causes the system to be electrically isolated from the external power source. A control circuit is responsive to actuation of the power switch to provide a signal to cause software control of a power state of the system.

主权项

1. A system comprising:
electrical components; a power supply to provide power to the electrical components; a momentary power switch to connect an external power source that is external to the system to the power supply, wherein the power switch has an on position, an off position, and a neutral position, and wherein the power switch if actuated to the off position causes the system to be electrically isolated from the external power source, wherein the power switch is to return to the neutral position after actuation to the on position; a latching relay to maintain electrical connection between the external power source and the power supply in response to actuation of the power switch to the on position, wherein the latching relay is to maintain electrical connection between the external power source and the power supply even though the power switch has returned to the neutral position; and a control circuit responsive to actuation of the power switch to the on position to provide a signal generated from a voltage provided by the power supply, the signal to cause machine-readable instructions to awaken the system from a system off state, and wherein the control circuit is to further provide the signal to the latching relay to actuate the latching relay to maintain the electrical connection.