| 摘要 |
PROBLEM TO BE SOLVED: To reduce a circuit scale and to reduce a cost by connecting a noise elimination function operation/suspension selection terminal through a resistor for deciding an oscillation frequency to a second potential by holding/opening the selection terminal to a first potential so as to control two states by one terminal. SOLUTION: In the case that a noise elimination function is not required, the terminal P is connected to VDD. The input A of a noise elimination circuit 2 becomes H at all times, the noise elimination circuit 2 is turned to a suspended state, and when output is present from an infrared ray sensor S, the pulses of a prescribed time width are immediately outputted to the terminal L. In the case that the noise elimination function is required, the terminal P is opened. Since the resistor R for deciding the oscillation frequency is connected to the terminal P, a transistor (f) is turned ON, an oscillation part 1 generates clocks and performs counting, and in the case that the output from the infrared ray sensor S is continued for prescribed time, it is defined that a human body is detected first, output is performed from the terminal L and a load is driven. |
