Pressure detection system on basis of programmable gain amplifier

Abstract

The invention discloses a pressure detection system on the basis of a programmable gain amplifier. The pressure detection system comprises a plurality of bridge type pressure sensors. A signal output end of each bridge type pressure sensor is connected with a signal input end of a pressure acquisition module by a low-pass filter, a signal output end of the pressure acquisition module is communicated and connected with a master control single chip microcomputer by a serial peripheral interface, and the master control single chip microcomputer is communicated and connected with an upper computer by an asynchronous transmitting and receiving transmitter inside the master control single chip microcomputer. The pressure detection system has the advantages that the programmable gain amplifier (PGA) is used as a preceding conditioning circuit for sensor signals, different gains can be adopted according to different requirements, full signal acquisition measuring ranges of the multiple sensors can be normalized, accordingly, the A / D (analog / digital) conversion available accuracy can be improved, and the purpose of processing the sensor signals without distortion can be achieved; circuit implementation schemes can be simplified, and the reliability and the stability of pressure data acquisition systems can be improved.

Description

technical field [0001] The invention relates to a pressure detection system, in particular to a pressure detection system based on a programmable gain amplifier. Background technique [0002] In automatic measurement and control systems and intelligent instruments, in order to ensure the necessary measurement accuracy, the pressure data acquisition system often uses pressure sensors of different ranges to collect pressure signals, and the analog output signal level ranges from microvolts to volts; and the general A It is impossible for the A / D converter to match it in all situations. If a single-gain amplifier circuit is used, the accuracy of the A / D converter will often not be utilized to the maximum, or the measured signal will be cut and saturated, resulting in A large measurement error may even damage the A / D converter. It is even more impossible for each sensor to have a dedicated A / D converter, which will greatly increase the design workload, and more importantly, inc...

AI Technical Summary

Problems solved by technology

Therefore, if you want to adapt to pressure sensors with different analog signal level output and ensure high precision, you must change the input and output impedance of the pre-filter circuit, select a suitable amplifier circuit to amplify the sensor signal, and use Appropriate A / D converters are used to complete the conditioning of sensor signals, which will increase the design workload and seriously increase the design cost

Moreover, the sensor signal conditioning circuit composed of discrete components requires more components, and the reliability is reduced; the peripheral circuit is complex, the circuit board area is large, the scalability is low, and the consistency of each circuit board during manufacturing is poor.

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