Patent ID: 7902839

Claim:
A power-control device comprising: a sensor unit including a sensor electrode, a conductive substrate that has an area larger than that of the sensor electrode, and a case formed of an insulating material, the conductive substrate being provided inside the case, the sensor electrode being electrically connected to the conductive substrate, the sensor unit that generates capacitance between a human body and a surface of the case when the human body touches the surface of the case; a detection unit that detects the capacitance and outputs an activation signal used to supply power; and wherein the detection unit includes a signal generating circuit that outputs a detection signal having a predetermined frequency, a delay circuit that generates a delay signal from the detection signal on the basis of a time constant, an AND circuit to which the detection signal and the delay signal are input, an integration circuit that integrates an output of the AND circuit, an analog-to-digital converter that converts an output of the integration circuit into a digital signal, and a comparator that compares an output of the analog-to-digital converter with a predetermined threshold, and outputs the predetermined activation signal on the basis of a result of the comparison.