Flush packaged pressure sensor with high temperature resistance and high frequency response

Abstract

The invention relates to a flush packaged pressure sensor with high temperature resistance and high frequency response, which comprises a pressure chip. The pressure chip is combined with a glass ring; the glass ring is adhered to a metal substrate; a high-temperature switching plate and a high-temperature switching circuit compensation plate are respectively fixed in the metal substrate; the pressure chip is connected with the high-temperature switching circuit compensation plate through a gold wire lead; the high-temperature switching plate is connected with the high-temperature switching circuit compensation plate through a high-temperature lead; a four-core high-temperature lead is connected with the high-temperature switching circuit compensation plate; the metal substrate is connected with a metal shell; the metal shell is connected with a wire-fixing cap; the four-core high-temperature lead passes through the metal shell and a hole of the wire-fixing cap; the pressure chip senses pressure from an external medium and converts a pressure signal into a voltage signal; and the voltage signal passes through the gold wire lead, the high-temperature switching plate and the high-temperature lead, is transmitted to the high-temperature switching circuit compensation plate, and is output through the four-core high-temperature lead after being compensated. The pressure sensor has the advantages of high temperature resistance and high frequency response, and is used for measuring dynamic or static pressure signals.

Description

technical field [0001] The invention relates to the field of pressure sensors, in particular to a flush-packaged high-temperature-resistant and high-response pressure sensor. Background technique [0002] As one of the most commonly used sensors, pressure sensors are widely used in aerospace, national defense, industry, petrochemical and other fields. In recent years, with the development of my country's aerospace and military industries, the demand for a pressure sensor with a frequency response of more than 100KHz and a high temperature resistance of more than 100°C is becoming more and more urgent. It is required to accurately measure the transient pressure in the process of aviation or blasting, because the accurate measurement of transient pressure and the undistorted waveform description of dynamic pressure play an extremely important role in the process of scientific experiments and design optimization demonstration. Therefore, the pressure sensor with wide frequency...

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Problems solved by technology

[0003] The current sensors for measuring pressure mainly include strain type, piezoelectric type and piezoresistive type. The natural frequency of the traditional strain type pressure sensor is too low to meet the needs of the test; the piezoelectric pressure sensor for dynamic pressure measurement also has its own Many disadvantages, the output of the piezoelectric pressure sensor is a charge signal, some piezoelectric materials require moisture-proof measures, and are prone to leakage of charge, and the subsequent processing circuit is more complicated, so it is necessary to use a high input impedance circuit or a charge amplifier to overcome this defect, cost High, and it is easy to introduce insurmountable noise. The piezoelectric pressure sensor can only measure the dynamic pressure signal, and it is powerless for the static and quasi-static pressure signal; it is made of the piezoresistive effect of silicon and integrated circuit technology. The traditional diffused silicon piezoresistive pressure sensor has the characteristics of high sensitivity, fast dynamic response, high measurement accuracy, good stability, easy miniaturization and mass production. When the operating temperature is higher than 80°C, the performance of the sensor will deteriorate or even fail due to the leakage current generated by the p-n junction. Therefore, it is difficult for the traditional diffused silicon pressure sensor to solve the problem of pressure measurement at a high temperature above 80°C, and the existing sensor chips are packaged in metal Inside the shell, there is a cavity, which reduces the frequency response of the sensor due to the lumen effect

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