A low-loss rectifier unit for inductive-powering of biomedical implants

Abstract

Biomedical implants have been developed in the recent years with a focus for continuous and real-time monitoring of physiological parameters. Battery-less operation of the implanted unit requires energy harvesting from an inductive link or from the neighboring environment. For efficient conversion of harvested energy to a usable DC level, a rectifier block is employed. However conventional CMOS full bridge rectifier incurs a significant amount of power loss and lowers the overall efficiency of the powering system. In this work a cross-coupled MOSFET based LC oscillator structure has been presented as a modified rectifier circuit. Cross-coupled structure minimizes the loss of the MOS switches and LC tank circuit boosts up the output DC level. The rectifier unit has been designed and simulated using 0.5-µm standard CMOS process. For simulation purposes, different biomedical frequency bands are used to validate the effectiveness of the proposed circuit. Simulation results show that the proposed rectifier circuit can achieve 75% PCE compared to the conventional full bridge CMOS rectifier of only 3% PCE.I.

A wireless-power and data-transfer using inductive RF link and ASK modulation

“…The IPDL comprises two resonating RLC circuits, namely, primary and secondary are as given in Figure 6 [15]. The primary one is placed externally and is called as external unit/device driven by an efficient 'Class-E' RF-power amplifier [16], while the other one is placed internally within the human body called as internal unit/device, supplied power from the exterior device in which some part of 'generated magnetic flux' from the exterior/primary unit (Tx coil) is coupled with internal part (Rx coil) that generates an inductive voltage as Rx coil which act as an antenna. To achieve higher power transfer efficiency, Tx and Rx coils are synchronized at point of same resonance frequency (4 MHz).…”

Tungsten Supported Plasmonic Nanoscale Absorber for Solar Thermal Photovoltaics Applications

“…It is very necessary to observe the angular response of the W-MMA because we do not know at which angle the input light will strike with the W-MMA. [111][112][113][114][115][116][117][118][119][120][121][122][123][124][125][126][127][128][129][130].…”

The research and application of embedded database encryption method

“…In the process ofimplementation ofthe experiment, this test used a structure to represent a database as folIows: enc_tank,that "info" represented arecord stored in the database, and the structure is as follows: database enc tank { key file "enc _tank.kO I" contains num; data file "enc _tank.dO 1" contains info; record info { unique key int num; int id; int enc_db; char enc_ch [12];…”