Biofeedback neuromuscular electrical stimulation front-end for dysphagia treatment

A dedicated front-end for biofeedback neuromuscular electrical stimulation (NESM) system is proposed. For controllable dysphagia treatment, the integrated circuit (IC) provides a stimulator front-end with programmable stimulation parameters (2μA-1mA current amplitude, DC-2KHz frequency, and variable duty cycle) and an electromyogram/impedance (EMG/ETI) readout front-end with programmable gain and bandwidth (42-80dB, 0.1Hz-1.2KHz) for biofeedback. Area-efficient, low-power but high precision current controlling is achieved by inducing the sigma-delta modulator technique in the stimulation channel. The measured impedance and EMG signal are used to determine the stimulation parameters, enabling a closed loop optimized treatment. The proposed front-end is fabricated in a 0.18 μm standard CMOS process technology and dissipates a peak power of 2.3 mW at the supply voltage of 1.8 V. Measurement results on a live person are also provided to validate the system´s effectiveness.