Design of signal conditioning circuit for linear displacement detection
When performing linear displacement detection using LVDT,an amplitude-modulated wave is output,with the amplitude reflecting the displacement size,but the direction of displacement cannot be determined.To address this issue,a signal conditioning circuit is proposed,mainly composed of a phase-sensitive detector and a low-pass filter.First,theoretical analysis,simulation design,and verification of the working principle of the circuit were conducted.Then,PCB circuits were designed and fabricated,and the waveforms at various test points of the circuits were tested and verified.Finally,it was applied to LVDT linear displacement measurement,with a measured sensitivity of S=-1.976 72 V/mm and a nonlinear error of γ=0.83％.Experimental results show that the phase-sensitive detector has the advantages of simple structure,convenient debugging,strong noise suppression capabilities,and high re-liability,enabling accurate detection and demodulation of signals.
万方数据
维普
