摘要:我们现在在工作和生活中会经常使用的电子秤这样一种电子测量工具。本文的设计是由电阻压力传感器和单片机等共同组成的。硬件方面主要是以电阻应变式传感器并采用全桥测量电路来实现对量程内物体进行称重，并实现报警功能，用数字LED显示，其中可以键盘输入，而软件方面则主要采用C语言。设计原理如下：使用等臂全桥测量电桥原理，将电阻式压力应变传感器的电阻转换成电压值，而传感器的电阻大小是由称重的物体重量来决定的。由于称重传感器输出的值是一个模拟量，相对小于A / D转换器的电压范围，所以在A / D转换前，需要进行放大和整形滤波处理。将放大后的输出电压信号经过A / D转换器转换成数字信号，并发送到单片机中，通过处理，控制数字驱动电路，最后用LED显示测量结果，实现称重功能。

关键词  压力传感器；单片机；A / D转换

Abstract:Now we are often use an electronic measuring instrument in work and in life such as electronic scale. The design jointly consists of resistance strain pressure sensor and single-chip microcomputer. Hardware design is mainly based on resistance strain pressure sensor and use the whole bridge measurement circuit to weigh the range of objects, and realize the alarm function, with LED digital display, which can use the keyboard input, furthermore software design is mainly using C language. Design principle is as follows: using the whole bridge measuring principle to convert resistance of resistance strain pressure sensor to voltage, and the resistance of the sensor size is determined by weighing the objects’ weights. Because of weighing sensor is an analog output value, relatively less than the voltage range of A/D converter, so before the A/D conversion, require amplifying and shaping filtering processing. Will the output voltage signal after amplification to convert the analog signal to digital signal after A/D converter, and sends it to the microcomputer, through the process, control the digital driving circuit, the last shows the measured results by means of the LED, then the weighting function is realized.

Keywords  Pressure transducer  Single-chip microcomputer  The A/D conversion