A 28-nm, 0.5-V, 78.5-nA Switched Capacitor Current Reference with Active Trimming for sub-1V Implantable Medical Devices

This work presents a 78.5-nA, 115-ppm/°C temperature coefficient, switched capacitor current reference for batteryless and US-powered implantable biomedical devices. It is also characterized by the presence of a trimming network that allows compensating the PVT variations. The circuit is designed in a 28-nm Bulk CMOS technology provided by TSMC and full post-layout characterization is provided. The proposed solution shows a 75.8-% power utilization, an overall power consumption of about 62 nW when operating under 0.6-V power supply the lowest area occupation compared with previous arts, making the circuit well suitable also for ultra-low power and sub-1V sensor nodes for the Internet-of-Things.