Circuit design for neural signal recording with cuff electrode

In this paper the development of a syetem for detecting and recording neural signals is presented. A kind of in-body implantable nerve electrode, called cuff electrode, is chosen as the interface between neural and electronic systems. An electronic circuit for processing the output signals from the cuff electrode is designed. The circuit includes an amplifier and a filter. An electrode system called true three is adopted to amplify the signals and eliminate the interference of electromoyographic (EMG). The simulation results show that the voltage gain is above 10(5) and the signal bandwidth is 30 kHz, the equivalent input noise is 9.219 x 10(-9) V/ and the total output noise is 8.804 x 10(-4) V/. A 2nd-order low-pass filter with a bandwidth of 4 kHz is used to diminish the noises interference. The circuit can amplify feeble signal of several microvolts and can be used to record neural signals.