Nonlinear correction system for bridge sensor

Abstract

The invention discloses a nonlinear correction system for a bridge sensor. The nonlinear correction system comprises a piezoresistive bridge sensor, a negative feedback circuit and an output gain amplifier, a negative feedback circuit is introduced to change the excitation voltage of the piezoresistive bridge type sensor and change the amplification factor of an output gain amplifier, so that an original bridge type nonlinear system is compensated; the negative feedback circuit comprises a summation module, a linearization digital-to-analog converter and a feedback amplifier which are connected in sequence, and the feedback voltage is applied to the feedback amplifier; the input end of the summation module receives feedback voltage amplified and converted by a feedback amplifier and a linearization digital-to-analog converter and reference voltage attenuated by an excitation coefficient respectively; excitation voltage output by the summation module is applied to the piezoresistive bridge type sensor. According to the invention, the nonlinear correction system is utilized to compensate the nonlinear characteristic of the piezoresistive bridge sensor, the nonlinear error can be reduced by 50 times, and a good linearization effect is achieved.

Description

technical field [0001] The invention belongs to the technical field of analog integrated circuits, and in particular relates to a nonlinear correction system for a bridge sensor. Background technique [0002] Existing pressure sensors have obvious nonlinear output when pressure is applied, that is, there is a nonlinear relationship between the pressure change and the output voltage signal of the pressure sensor within its range, which will affect the function and accuracy of the pressure acquisition system. Existing linearization techniques are: [0003] Compensation methods for hardware circuits usually use analog circuits and digital circuits, such as diode array square rooters, various logarithmic, exponential, trigonometric operational amplifiers, and other digitally controlled segmental corrections, nonlinear A / D conversion, etc. This method mainly uses nonlinear devices or the nonlinear region of certain components, such as placing diodes or triodes in the feedback lo...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a nonlinear correction system for bridge sensors, which solves the problem of nonlinear output of existing sensors

Images