VLSI implementation of wireless bi-directional communication circuits for micro-stimulator

This paper presents the integrated circuit design for a wireless bi-directional transmission micro-stimulator. This implantable device includes an internal RF front-end circuit, a control circuits, a stimulator, and an on-chip transmitter. The operation of this system is to receive a 2 MHz AM modulated signal generated by external circuits. This signal includes the power and data necessary for the whole internal circuits. Through the internal circuits, a stable DC voltage and digital data can be extracted to stimulate neuromuscular stimulation. Besides, the system can acquire the biological sensing signal by means of on-chip transmitter. In this study, most of the integrated circuits for the implantable device have been verified by using Hspice according to the technology of TSMC 0.25 um CMOS process.