A Wirelessly Powered Reconfigurable FDD Radio with On-Chip Antennas for Multi-Site Neural Interfaces

This article presents a fully integrated, wireless, RF-powered data transceiver for high-performance implants, such as neural interfaces. The design occupies a total volume of 1.6 mm3 with no need for an off-chip component. The integrated circuit (IC) receives power and downlink data with amplitude-shift-keying (ASK) modulation by an on-chip coil through an RF wireless link. For uplink data transmission, we designed a transmitter (TX) based on a power oscillator stage directly connected to an on-chip dipole antenna that supports various data rates with both on-off-keying (OOK) and ultrawideband (UWB) schemes. The radio includes a power receiver (RX) system that enables the IC to operate under various power budgets by adjusting the duty cycle of the TX. With a 25-dBm power TX at a 1-cm distance, the RX achieves a maximum data rate of 2.5 Mbps with a power consumption of 2.6 μW. Also, the TX supports data rates of up to 150 Mbps with UWB modulation with a 15-cm operating range achieving an energy efficiency of 4.7 pJ/b. This work improves RX and TX energy inefficiencies by × 50 and × 2.3 , respectively.