A 11μW Sub-pJ/bit reconfigurable transceiver for mm-sized wireless implants

A wirelessly powered 11 μW transceiver for implantable sensors has been designed and demonstrated through 35 mm of porcine heart tissue. The prototype occupies 1 mm × 1 mm in 65nm CMOS with an external receive antenna. The IC consists of a rectifier, regulator, demodulator, modulator, controller, and sensor interface. The forward link transfers power and data on a 1.32 GHz carrier using low-depth ASK modulation that minimizes impact on power delivery and achieves from 4 to 20 Mbps with 0.3 pJ/bit at 4 Mbps. The backscattering link modulates the antenna impedance with a configurable load for operation in diverse biological environments and achieves 2 Mbps at 0.7 pJ/bit. The device supports TDMA, allowing for simultaneous operation of multiple sensors.