摘要 |
<p>An on/off control circuit is provided that controls the application of power to a device. The effectiveness of the on/off control circuit is optimized with regard to cost, power consumption, component life, and utility. An R-C circuit is used to provide a time-delayed turn-on, and turn-off, of the device being controlled, accompanied by a latch that retains the on/off state and controls the coupling of a power source to the device being controlled. The latch is configured as a data flip-flop (DFF) with a clocking signal that is controlled by the time-delayed switch input. The flip-flop has an inverted output signal as its input, thereby providing a toggled on/off operation. The latch also includes an independent reset input, thereby allowing an independent turn-off operation by power management controllers within the device being controlled. In the quiescent state, the preferred embodiment consumes less than half a microWatt of power.</p> |