Search results for " CIRCUIT"
showing 10 items of 634 documents
Current characterisation for ultra low power wireless body area networks
2010
The emerging area of body area networks (BAN) imposes challenging requirements on hardware and software to achieve the desired lifetimes for certain devices such as long term medical implants. In this paper, we propose a novel approach to the measurement and characterisation of the energy consumption of BAN devices. The approach uses a low cost energy auditing circuit and addresses the problem of accurately measuring low-level current consumption. This new technique will allow precise and analytical measurements of systems and components in terms of energy. This will help circuit designers minimise power consumption in BAN devices. Software engineers might use this approach to validate and …
Novel zero-current-transition circuit for three-phase buck rectifiers
2002
ZCT circuits have already been proposed in the past and are becoming more and more popular in high power rectifiers and inverters where bipolar devices have to be used (IGBTs or even BJTs). Although ZCT techniques have already been applied to three-phase boost type topologies, no ZCT circuits have been proposed for three-phase buck-type topologies. The authors propose a new load independent ZCT circuit for a three-phase buck-type rectifier which achieves high noise reduction, voltage stress reduction and zero current transitions to almost all transitions of the rectifier's switches including the additional auxiliary switches.
On the de-energization of over-head low-voltage lines under high-impedance fault conditions
2018
Downed distribution conductors in overhead distribution systems, may not be a concern for equipment, but greatly challenge the safety of persons, as well as the integrity of properties. Upstream overcurrent protective devices may not be able to detect the magnitudes of fault currents resulting from these high-impedance faults. Even though protective devices capable to detect such faults have been available on the market, not all the utilities have equipped their stations with these products, likely due to the costs. In this paper, the authors formalize the problem, and propose a possible cost-effective solution for the low-voltage over-head lines with neutral wire. Such solution includes a …
Optoelectronic Module with Integrated Transceiver and Mux-Demux for Optical Interconnect Applications
2019
The design, development and improvtableement in electronic devices and components have led to the further miniaturization of the system devices and their interconnecting interfaces. Hence, reducing the size of the transmitter (Tx) chips, receiver (Rx) chips and associated components play an important role in designing a reduced/small sized optoelectronic modules for optical interconnect applications. Some of the associated components include multiplexer, demultiplexer, clock and data recovery circuits (CDR), etc. Therefore, in this paper we present an optoelectronic module with integrated transceiver (Tx-Rx) and multiplexer-demultiplexer (mux-demux) with the aim of reducing the total area o…
A wireless battery charger architecture for consumer electronics
2012
In this paper, an innovative design of a wireless battery charger for portable electronic devices is proposed. The wireless power transfer is implemented through the magnetic coupling between a power transmitter, which is connected to the grid, and a power receiver, which is integrated inside the load device. An innovative receiver architecture which heavily improves the power conversion efficiency is presented. The proposed solution is standard compliant and suitable for IC implementation. A comparison between a conventional and the proposed receiver architectures is carried out by SPICE simulations. As shown by simulation results, a power efficiency increase by 40% is provided by the prop…
A lossless current sensing technique for flyback converters
2009
Regardless of the feedback control, almost all converters require input or output current sense for overcurrent protection. If a current mode control is implemented, high accuracy is also required. The optimal current sensing method shows the highest accuracy and the lowest power dissipation. In this paper, a lossless and accurate current sensing technique for Flyback converters is proposed. An RC network is parallel connected with the primary MOSFET and the voltage signal across the sense capacitor accurately reproduces the magnetizing current waveform. The RC technique benefits from all the advantages of the most common current sensing techniques currently applied to Flyback converters, a…
Basic Concepts of Power Distribution Network Design for High-Speed Transmission
2011
This paper tries to gather the Power Distribution Network (PDN) techniques used to preserve power integrity in PCB designs when transmitting data rates over 6 Gbps using the newest commercial optical modules. The PDN design described allows for proper impedance control of the power supply with the appropriate choice of the number, location and values of capacitors. This method needs the knowledge of the electrical RLC model of the regulators, copper planes, capacitors and vias used in the PCB. A particular case of PDN design will be presented for a module using one SNAP12 optical transmitter and one receiver connected to an Altera Stratix II GX FPGA. This board is designed to work with data…
A prototypal PCB board for the EMI characterization of SiC-based innovative switching devices
2020
In this paper, a preliminary PCB board for the electromagnetic interference (EMI) characterization of innovative silicon-carbide (SiC) based switching devices is presented. Packaging technological issues can determine hurdles in the high-frequency switching and high power regime where wide band gap semiconductors are intended today for Electric Vehicle (EV) applications. In particular, the parasitic inductances that emerge in such devices, must be assessed, by using e.g. EMI techniques. In this specific case, the EMI characterization is supposed to be carried out in a semi-anechoic chamber, available at the University of Palermo (UNIPA), to assess the electromagnetic disturbances according …
Simulation of parasitic effects on Silicon Carbide devices for automotive electric traction
2020
Wide Band Gap (WBG) semiconductors are increasingly addressed towards Electric Vehicle (EV) applications, due to their significant advantages in terms of high-voltage and low-losses performances, suitable for high power applications. Nevertheless, the packaging in WBG devices represents a challenge for designers due to the notable impact that inductive and capacitive parasitic components can bring in high switching frequency regime in terms of noise and power losses. In this paper, a comparison between conventional Silicon (Si) and emerging Silicon-Carbide (SiC) power switching devices is presented. The effects of inductive parasitic effects and switching frequency are investigated in simul…
A Secure Spontaneous Ad-Hoc Network to Share Internet Access
2009
In this paper, we propose a secure spontaneous ad-hoc network to grant the access of the users to surf the Web. The paper shows the description of our proposal, the procedure of the nodes involved in the system and the designed messages. We also validate the success of our proposal through several simulations and comparisons with a regular architecture. The proposal has been developed with the main objective of improving the communication and integration between different study centers of low resource communities.