Inductor

About: Inductor is a research topic. Over the lifetime, 52565 publications have been published within this topic receiving 484068 citations. The topic is also known as: passive two terminal.

Single inductor dual output buck converter with frequency and time varying offset control

Abstract: A single-inductor dual-output buck converter and control method that facilitates power conversion by converting a single DC power source/supply into two separate DC outputs, each of which can be configured to provide a selected/desired voltage by selection of respective duty cycles. The topology of the inverter includes a pair of diodes or switches that can selectively re-circulate inductor current. The converter is generally operated at a fixed frequency with four stages of operation. A first and third stage of operation provide power to a first and second output, respectively. A second and fourth stage of operation re-circulate inductor current and can partially recharge a battery type power source. The power output for each stage (voltage and current) can be selectively obtained by computing and employing appropriate time periods for the stages of operation that correspond to appropriate duty cycles.

A comparative analysis of Switched-Capacitor and inductor-based DC-DC conversion technologies

Abstract: This paper compares the performance of Switched-Capacitor (SC) and inductor-based DC-DC conversion technologies. A metric to compare between the two topologies is discussed, and is used to compare switch utilization. Fundamental limits on utilization of reactive elements developed in the literature for all DC-DC converters are also reviewed and discussed, and this analysis shows that popular SC and inductor-based converters achieve the limits of utilization for reactive components. These limits are stated in terms of the ratio of output power to required stored energy in reactive elements. A detailed analysis of available surface mount discrete components and on-die devices reveals that capacitors have substantially higher energy and power density than their magnetic counterparts. The challenging regulation task for SC converters is also discussed, with a promising strategy outlined. The SC converter is evidently a promising candidate for future high power density integrated DC-DC converters.

Electrically controlled elasticity utilizing piezoelectric coupling

Abstract: Electrical control of elasticity was performed in piezoelectric polymer films by connecting an electric circuit parallel to the sample electrodes. A polyvinylidene fluoride film and a vinylidene fluoride tetrafluoroethylene copolymer (73/27) film were used. Electrical circuits acting as a variable negative capacitor or a variable inductor were constructed using operational amplifiers. Theoretically, when the value of the external negative capacitance is increased, the observed elastic constant increases from that at an open circuit to positive infinity at around the value of the sample, turns to negative infinity, and then increases through zero to that at a short circuit. If the inductance of the external circuit is changed around the electrical resonant frequency, the elastic constant exhibits resonance and antiresonance against frequency. Experimental observations of the characteristics of the dynamic elastic constant agreed well with these theoretical predictions. By coupling the negative capacitance, the elastic constant changed between 0.5 and 2 times the original value, and the elastic loss increased to tan δ=0.7.

High-frequency small-signal model of ferrite core inductors

Abstract: A circuit model of ferrite core inductors is presented. The behavior of the model parameters versus frequency is considered. The total power loss in inductors consisting of the winding resistance loss and the core loss, is modeled by a frequency-dependent equivalent series resistance. The total inductance given by the sum of the main inductance and the leakage inductance is obtained as a function of frequency. In order to study the core equivalent resistance and main inductance versus frequency, the magnetic field distribution in the core is derived from Maxwell's equations for a long solenoid. The complex permeability and permittivity of the ferrite core are introduced in the electromagnetic field equations. Experimental results are also given.

Radio frequency identification tag on a single layer substrate

Abstract: A radio frequency identification (RFID) tag on a single layer substrate comprises a semiconductor integrated circuit RFID tag device and antenna circuit. A connection jumper may be used to bridge over the antenna circuit coil turns. The RFID tag device is located on the same side as an inductor coil and capacitor which forms a parallel resonant antenna circuit. The inductor coil has an inner end and an outer end. The inner or outer end may be connected directly to the RFID tag device and the outer or inner end be may connected to the RFID tag device with a jumper over the inductor coil turns, or the RFID tag device may bridge the inductor coil turns when being connected to both the inner and outer ends. An encapsulation (glop top) may be used to seal the RFID tag device and jumper, and an insulated coating may be used to cover the entire surface of the substrate to create an inexpensive “chip-on-tag.” The encapsulation may be epoxy, plastic or any protective material known to one of ordinary skill in the art of electronic circuit encapsulation. The insulated coating may be of any type suitable for the application of use of the RFID tag.