Simple LVDT signal conditioner

A method to implement a signal conditioning circuit for a linear variable differential transformer (LVDT) is proposed in this article. The proposed signal conditioner can be used instead of a synchronous demodulator in the tradition approaches. The output signal of the signal conditioner is linearly proportional to the moving core of the LVDT with fast response. The realization technique is based on the use of an analog integrator to determine the LVDT signal at the half period of the excitation signal. The proposed signal conditioner provides without low-pass filter in the signal path. Therefore, the response time of the proposed technique is settled within half period of the excitation signal. The devices used in the proposed signal conditioner consist of basic commercially available devices such as operational amplifier (opamp), comparator, analog switch and one-shot timer. Experimental results demonstrated the performance of the proposed conditioner are included. The proposed technique is attractive in terms of simple configuration and low cost.