An inside body power and bidirectional data transfer IC module pair

An IC module pair connected with 3 wires was proposed for an implant that consisted of a master unit (MU) and a small, light-weight satellite unit (SU). Power was delivered from the MU to the SU using a 3-phase signal, and converted to DC in the SU by a passive MOS AC-DC converter. Data transfer between the two units was achieved by modulating the amplitudes and the positions of the rising and falling edges of the 3-phase signal. A bidirectional data rate in the range of MB/s and an overall power efficiency of 90.2% for a 3.2mW load were achieved in a 0.18μm CMOS process.