Analog quantity conditioning and distributing device with high precision and all-digital calibration

Abstract

The invention discloses an analog quantity conditioning and distributing device with high precision and all-digital calibration, which comprises an instrumentation amplifier, an isolation amplifier, a verification module and an output drive module, wherein the instrumentation amplifier is used for receiving and treating field signals; the isolation amplifier is used for receiving the field signals processed by the instrumentation amplifier and then performing isolation output on the field signals; the verification module is used for receiving and verifying the signals output by the isolation amplifier; the output drive module is used for receiving the signals from the verification module and outputting the signals to a corresponding system; the verification module is connected with a general calibration device which is used for verifying the field signals output by the verification module; the general calibration device comprises an upper computer controlling the verification process and a calibration instrument controlled by the upper computer to generate standard voltage and current signals and transferring the standard voltage and current signals to the verification module; the upper computer is connected with the verification module through an SPI (serial peripheral interface); and the output drive module is connected with the calibration instrument. According to the invention, a digital potentiometer is adopted to replace a mechanical potentiometer, and the digital potentiometer is operated to change value of resistance through the SPI, so that detuning and linear error of the analog quantity conditioning and distributing device can be eliminated.

Description

technical field [0001] The invention relates to the field of signal acquisition, in particular to an analog quantity acquisition, conditioning and distribution device for acquiring and distributing analog signals and realizing full digital calibration. Background technique [0002] In many industrial sites, when different systems are connected, it is hoped that the signals of both parties will not affect each other. In particular, the system failure of one party will not damage the normal operation of the other party. In this case, it is usually necessary to isolate the signal before connecting it. At the same time, signal isolation can also eliminate the impact of ground loops. The main function of the analog signal conditioning and distribution device is signal isolation and signal distribution, and it is used in occasions where on-site signals need to be transmitted to multiple different systems. The input of the analog signal conditioning distribution device is a 0~20m...

AI Technical Summary

Problems solved by technology

[0007] In order to solve the problems of large errors, low efficiency and poor reliability in the prior art when using a mechanical potentiometer to adjust an analog conditioning circuit, the present invention provides a digital potentiometer to adjust an analog conditioning circuit. Conditioning device, the specific plan is as follows: high-precision all-digital calibration analog conditioning and distribution device, including the instrumentation amplifier that receives the field signal and processes it, and the isolation amplifier that receives the field signal processed by the instrumentation amplifier and isolates it for output. Isolate the signal output by the amplifier and verify the verification module, receive the signal of the verification module and output it to the output drive module of the corresponding system, it is characterized in that the verification module is connected with a verification module for verifying the field signal it outputs A universal calibration device, which includes a host computer that controls the calibration process and a calibrator that is controlled by the host computer to generate standard voltage and current signals and transmits them to the calibration module. The host computer is connected to the calibration module through an SPI interface, The output drive module is connected to the calibrator

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