【摘要】 目前大多数防盗报警系统都利用电磁波或红外线辐射来检测人体移动,这两种报警系统都因有发射和接收电路而结构复杂,价格昂贵。针对这种状况,本文介绍了一种新型防盗报警电路设计方法。该设计利用人体作为感应电容的一个极板,借助高精度电压比较器MAX912检测感应电容的变化。同时该电路还具有双门限检测报警功能,采用震动传感器感受震动信号,利用单片机设置告警距离和持续时间双门限。测试结果表明该电路结构简单,性能稳定,已成功用于某防盗报警系统中。更多还原

【Abstract】 Most of alarm systems against theft make use of electromagnetic wave or infrared emitting to detect the movement of hu-man body,these circuits are complicated and prices are also expensive because of transmitting and receiving circuits,According to the situation,a new design method is introduced in this paper.Human body is served as an induction capacitor which capacitance is de-tected by the voltage comparator MAX912 with high accuracy in the circuit.It uses sensor to detect the vibration signals,and sets double thresholds –the alarm range and the durative time.So it can make alarm under the detecting of double thresholds.The cir-cuit is simple and stable,Now it is used successfully in a certain alarm system against theft.更多还原