Thimot, Jordan, Kukjoo Kim, Chen Shi, and Kenneth L. Shepard. “A 27-Mbps, 0.08-mm3 CMOS Transceiver with Simultaneous Near-field Power Transmission and Data Telemetry for Implantable Systems.” In 2020 IEEE Custom Integrated Circuits Conference (CICC), pp. 1-4. IEEE, 2020.
This paper describes an inductively powered 27-Mbps, 0.08-mm3 CMOS transceiver with integrated RF receivercoils for simultaneous two-way, near-field data telemetry andpower transmission for implantable systems. A four-coil inductivelink operates at a 27-MHz carrier for power and a 700-MHzcarrier for data telemetry with the antennae taking an area of only2 mm by 2 mm. Amplitude-shift-keying (ASK) modulation is usedfor data downlink at 6.6 kbps and load-shift keying (LSK)backscattering is used for data uplink at 27 Mbps. The transceiverconsumes 2.7 mW and can power a load consuming up to anadditional 1.5 mW. Implemented in a 0.18-um silicon-on-insulator(SOI) technology, post-processing steps are used to decrease chipthickness to approximately 15um, making the chip flexible with atissue-like form factor and removing the effects of the substrate oncoil performance. Power harvesting circuitry, including passiverectifier, voltage regulator, RF limiter, ASK and LSK modulator,clock generator, and digital controller are positioned adjacent tothe coils and limited to an area of 0.5 mm by 2mm. Completetransceiver functionality of the system has been achieved withoverall power transfer efficiency (PTE) of 1.04% through 1 mm oftissue phantom between reader and implant.