In the chemical industry, military experiments, university experiments and other experimental conditions involving chemical explosion, it is often necessary to monitor the fluctuation process of dynamic pressure generated by the explosion moment. It requires that the pressure sensor must have a very high response frequency and a very fast rise time, in order to accurately measure the instantaneous pressure change process.
The response frequency of a pressure sensor depends on three important factors: 1. The natural frequency of the sensor. 2. The packaging mode of the sensor. 3. Frequency response bandwidth of the transformer circuit.
First of all, the natural frequency of the sensor depends on the physical properties of the materials and structure of the sensor sensitive element, which has been finalized during the production process of sensor chip and cannot be changed through later treatment. Therefore, natural frequency is generally only used as a physical index of parameters of the dynamic pressure transducer, which has no great practical significance in the selection and application of sensor.
Secondly, the packaging of sensor is an important process to determine the sensor response frequency. If the sensor chip with the same natural frequency adopts different packaging mode, the frequency response range that the sensor can be used may be directly affected.
Thirdly, when the sensor is packaged, it is necessary to co-work with the subsequent acquisition equipment to realize the reproduction of dynamic pressure. Therefore, dozens of millivolts tiny signal will often receive the amplification processing and is converted into standard voltage signal. In this conversion process, the circuit is required to have high enough response bandwidth and short enough rise time, so as to reproduce the distortionless pressure change process.