A Current Monitoring and Over-Current Detection Circuit for Safe Electrical Stimulation

This brief presents an integrated solution to over-current protection in neuromuscular stimulators. The proposed approach provides fast detection of a single-fault condition, i.e., unintentional electrode short circuit or malfunction of the stimulator, thereby preventing prolonged high-intensity currents from flowing into tissues. In addition, a programmable current threshold enables the system to be also used for monitoring the stimulation intensity. The proposed solution was designed in a 180 nm high-voltage CMOS technology, and its functionality was verified by post-layout simulations in which the safety mechanisms were tested under fault conditions. The implementation only occupies an area of 0.286 mm(2), making it feasible to be embedded in fully integrated NMES stimulators while providing the required patient safety.

Automated summary

This brief presents an integrated solution for over-current protection in neuromuscular stimulators. It provides a fast detection of single-fault conditions and a programmable current threshold for stimulation intensity monitoring. The proposed solution was designed in a 180 nm high-voltage CMOS technology with verified functionality through post-layout simulations. It occupies a small area of 0.286 mm(2), making it suitable for fully integrated NMES stimulators with patient safety.