| 摘要 |
PURPOSE: An RF oscillation type proximity sensor with improved noise resistance is provided to prevent malfunction by removing a noise within a preset range when an external noise is inputted. CONSTITUTION: An LC oscillator(110) includes an LC resonance circuit(111) and a level shifter which shifts a signal outputted from the LC resonance circuit. A demodulator(120) includes a first reference voltage generator(121), a first comparator which outputs a square wave or low signal, a transistor, and a capacitor. The first comparator compares the reference voltage with the level-shifted signal. A hysteresis comparator(130) includes a second reference voltage generator(131) and a second comparator which outputs high/low signals. |
