火箭测试平台多通道脉动压力微弱信号调理电路设计

目的实现火箭测试平台多通道脉动压力微弱信号调理电路设计。方法基于高性能仪表放大器进行低噪声放大电路设计,仪表放大器输入端引入RFI滤波器,抑制射频干扰,显著减小电路输出噪声。模拟信号输出端集成ADC转换单元,实现模拟信号的数字化传输,进一步降低模拟信号传输干扰。实现信号调理电路小型化设计,将4个通道脉动压力信号调理电路集成到一块40 mm×35 mm的电路单板,实现对4个通道脉动压力传感器的供电、信号调理及数字化等功能。通过多个单板的组合化设计,实现多通道脉动压力信号调理电路设计。结果获得了信号调理电路的本底噪声水平,通过风洞试验验证了信号调理电路设计的正确性。结论设计的多通道脉动压力微弱信号调理电路可应用于火箭测试平台,具有抗干扰、小型化、组合化等特点。

Design of Multi-channel Weak Signal Conditioning Circuit for Fluctuating Pressure of Rocket Test Platform

The purpose of this study is to design the weak signal conditioning circuit for multi-channel fluctuating pressure of rocket test platform. The low noise amplifier circuit is designed based on high performance instrument amplifier. An RFI filter is introduced into the input terminal of the instrument amplifier to suppress RF interference and significantly reduce the output noise of the circuit. Furthermore, ADC conversion unit is integrated with the analog signal output terminal to realize the digital transmission of analog signals and further reduce the interference in the analog signal transmission. The signal conditioning circuit is miniaturized and integrated into a single 40 mm×35 mm circuit board to realize the functions of four-channel fluctuating pressure sensor power supply, signal conditioning and digitization. The multi-channel signal conditioning circuit is created through the combination of multiple single boards. The background noise level of the signal conditioning circuit is obtained, and the design of signal conditioning circuit is verified by wind tunnel test. Characterized by anti-interference, small size and combined circuits, the multi-channel weak signal conditioning circuit can be applied to the rocket test platform.