Title :
A High-Efficiency Low-Voltage CMOS Rectifier for Harvesting Energy in Implantable Devices
Author :
Hashemi, S.S. ; Sawan, M. ; Savaria, Y.
Author_Institution :
Electr. Eng. Dept., Ecole Polytech. de Montreal, Montreal, QC, Canada
Abstract :
We present, in this paper, a new full-wave CMOS rectifier dedicated for wirelessly-powered low-voltage biomedical implants. It uses bootstrapped capacitors to reduce the effective threshold voltage of selected MOS switches. It achieves a significant increase in its overall power efficiency and low voltage-drop. Therefore, the rectifier is good for applications with low-voltage power supplies and large load current. The rectifier topology does not require complex circuit design. The highest voltages available in the circuit are used to drive the gates of selected transistors in order to reduce leakage current and to lower their channel on-resistance, while having high transconductance. The proposed rectifier was fabricated using the standard TSMC 0.18 μm CMOS process. When connected to a sinusoidal source of 3.3 V peak amplitude, it allows improving the overall power efficiency by 11% compared to the best recently published results given by a gate cross-coupled-based structure.
Keywords :
CMOS integrated circuits; biomedical equipment; capacitors; energy harvesting; leakage currents; rectifiers; transistors; bootstrapped capacitor; channel on-resistance; energy harvesting; full-wave CMOS rectifier; gate cross-coupled-based structure; high-efficiency low-voltage CMOS rectifier; implantable device; leakage current; load current; low voltage-drop; low-voltage power supply; rectifier topology; selected MOS switch; size 0.18 mum; standard TSMC 0.18 μm CMOS process; transconductance; transistor; voltage 3.3 V; wirelessly-powered low-voltage biomedical implant; CMOS process; Capacitors; Logic gates; MOSFETs; Threshold voltage; Topology; Bioelectronics; bootstrapping technique; implantable devices; low-voltage devices; power efficiency; rectifiers; Biomedical Engineering; Computers; Electric Capacitance; Electric Power Supplies; Electronics; Equipment Design; Humans; Prostheses and Implants; Signal Processing, Computer-Assisted; Transistors, Electronic; Wireless Technology;
Journal_Title :
Biomedical Circuits and Systems, IEEE Transactions on
DOI :
10.1109/TBCAS.2011.2177267
