An Area-Efficient Rectifier with Threshold Voltage Cancellation for Intra-Body Power Transfer

In this paper, the feasibility of the intra-body power transfer is verified and an area-efficient rectifier with threshold voltage cancellation for intra-body power transfer is proposed. Through the measurement, the optimum power transmission frequency is determined as 1 MHz. Since the transmission voltage gain is sufficiently high (about 0.3) and nearly constant over a wide range of the load resistance, the intra-body power transfer works well even with the nonlinear and varying input impedance of the rectifier that is placed right after the receiving electrode. The proposed area-efficient rectifier cancels the threshold voltage by using a diode-connected device with a dynamically biased current source. It achieves a considerably smaller area of 65 μm × 30 μm than the area consumed by other designs reported previously. The overall power conversion efficiency (PCE) and voltage conversion ratio (VCR) are also improved. It achieves 84.4% of PCE and 85.6% of VCR with 1-V input voltage and 40-kΩ load.

[1]  Mohamad Sawan,et al.  A High-Efficiency Low-Voltage CMOS Rectifier for Harvesting Energy in Implantable Devices , 2012, IEEE Transactions on Biomedical Circuits and Systems.

[2]  Yu-Te Liao,et al.  A 3-$\mu\hbox{W}$ CMOS Glucose Sensor for Wireless Contact-Lens Tear Glucose Monitoring , 2012, IEEE Journal of Solid-State Circuits.

[3]  Maysam Ghovanloo,et al.  A Q-Modulation Technique for Efficient Inductive Power Transmission , 2015, IEEE Journal of Solid-State Circuits.

[4]  Tolga Soyata,et al.  RF Energy Harvesting for Embedded Systems: A Survey of Tradeoffs and Methodology , 2016, IEEE Circuits and Systems Magazine.

[5]  Hoi-Jun Yoo,et al.  A 48 μW, 8.88 × 10−3 W/W batteryless energy harvesting BCC identification system , 2016, 2016 IEEE International Symposium on Circuits and Systems (ISCAS).

[6]  Harinath Garudadri,et al.  Channel Modeling of Miniaturized Battery-Powered Capacitive Human Body Communication Systems , 2017, IEEE Transactions on Biomedical Engineering.

[7]  Minkyu Je,et al.  High-Efficiency Wireless Power Transfer for Biomedical Implants by Optimal Resonant Load Transformation , 2013, IEEE Transactions on Circuits and Systems I: Regular Papers.

[8]  Mahmoud Kamarei,et al.  Transient Input Impedance Modeling of Rectifiers for RF Energy Harvesting Applications , 2018, IEEE Transactions on Circuits and Systems II: Express Briefs.

[9]  K. Kotani,et al.  High-Efficiency Differential-Drive CMOS Rectifier for UHF RFIDs , 2009, IEEE Journal of Solid-State Circuits.

[10]  Anantha Chandrakasan,et al.  Platform architecture for solar, thermal and vibration energy combining with MPPT and single inductor , 2011, 2011 Symposium on VLSI Circuits - Digest of Technical Papers.