摘要：随着科技的不断发展，气压计技术也在不断的进步和创新，气压计被广泛应用于国防领域、工业领域、医疗领域以及日常家庭生活中。传统的水银气压计和无液气压计体积比较大，测量结果不够准确，容易受到周围环境的影响，已经无法满足远距离传输以及在恶劣环境下的操作。因此，数字气压计的出现成为了必然。本文根据所查阅的文献资料介绍了基于气压传感器MPX4115的数字气压计。通过利用气压传感器MPX4115获得与大气压相应的模拟电压值，在经过电压/频率（V/F）转换模块转换为数字脉冲，经过一定处理后得到实际的气压值。最后由数码管电路显示出来。并且提出了电路的软硬件设计方案，其中软件部分利用Proteus软件实现电路的仿真，用C语言编写程序实现此设计的全部功能。

关键词：气压传感器； 电压/频率转换； 单片机

Abstract：With the continuous development of science and technology, barometer technology is also in constant progress and innovation. The barometer has been widely used in the defense sector, industrial sector, the medical field as well as day-to-day family life. Traditional mercury barometer and the aneroid barometer volume is relatively large, the measurement results are not accurate enough, and vulnerable to the influence of the surrounding environment，which has been unable to meet the long-distance transmission and operate in the harsh environment. Therefore, the emergence of the digital barometer has become inevitable.This article has introduced a digital pressure meter which based on the pressure sensor MPX4115. Analog voltage value corresponding to the atmospheric pressure by the pressure MPX4115, after the voltage/frequency (V/F) converter module is converted to digital pulse, after a certain treatment we can find the actual pressure value. Finally, it will be displayed by the digital control circuit. And we made a circuit of hardware and software design solutions in this paragraph. One part of the software is used the Proteus software to meet the circuit simulation program. The whole program is written in C to achieve the full functionality of this design.

Key words:  Pressure sensor； Voltage / frequency conversion； SCM