Patent ID: 7319282

Claim:
A switch circuit for controlling the supply of electrical power from an electrical power source to a load, the switch circuit comprising a power supply switch having input, output and control terminals, wherein the input terminal of the power supply switch is coupled to the electrical power source and the output terminal of the power supply switch is coupled to the load; an electronic switching device connected to the control terminal of the power supply switch and having an activating input; a momentary switch coupled to the activating input of the electronic switching device; a charge storage element coupled to the momentary switch; the arrangement being such that (i) in a first mode, power is supplied to the load by closing the momentary switch to connect the charge storage element to the electronic switching device for a predetermined time in excess of a triggering time of the electronic switching device, the predetermined time being determined by the charge-up time of the charge storage element and triggering of the electronic switching device maintaining the power supply switch in an on state to supply power from the electrical power source to the load; and ii) in a second mode, the supply of power to the load is stopped by closing the momentary switch to connect the charge storage element to the electronic switching device, the charge storage element providing a signal to turn off the electronic switching device and the power supply switch to cut the supply of power from the electrical power source to the load.