50 results about "Self resonance frequency" patented technology

A differential inductor is formed from branch coils that are staggered with respect to one another rather than concentrically coiled within one another. Each coil is formed from conductive strips. The conductive strips with the largest voltage swings thereon are shielded from one another by conductive strips with lower voltage swings thereon. This shielding allows the effective capacitance of the differential inductor to be lowered, which in turn raises the range of frequencies at which the differential inductor can operate.

The invention belongs to the technical field of electronic components and relates to a multi-layer chip filter and a preparation method thereof. The filter leads in ceramics and ferrite in the same chip and simultaneously realizes large inductance and large capacitance; wherein, the inductance consists of a hollow inductance (a 'magnetic core' is a ceramic material) and a magnetic core induction (the magnetic chip is ferrite material). The hollow inductance is characterized by small inductance value, large quality factor, high self-resonance frequency, and the like, thus being capable of better broadening the working frequency section of the filter; the magnetic core inductance has the characteristics of large inductance value, low self-resonance frequency, and the like, thus better reducing the in-band insertion loss of a filter with a low cut-off frequency and improving the effect of the transmission signal of the filter. The preparation method of the multi-layer chip filter includes the steps such as material preparing, casting, punching, pore filling, conductor printing, chip overlapping, isostatic pressing, gumming, sintering, etc. The filter has the advantages of small size, large rectangle degree, large out-band rejection as well as broad working frequency. The preparation method has high controllability and can be compatible with the technique of the existing chip components.

The invention relates to a method for preparing a high-frequency ferromagnetic film material with component gradient under the room temperature condition. The invention adopts the proposal that in a vacuum thin film gradient sputtering device, a ferromagnetic material is adopted as a main material target and arranged below a sputtered base plate; simple substances, oxides, nitrides, borides, carbides or phosphides are taken as adulterants to be arranged at the position outwards deviated from the center of the base plate, during the sputtering, the components of the main material target form an even film on the base plate, and the components of an adulterant target form a film provided with the components of the adulterants and distributed in gradient form along a certain direction. The invention adopts the design that the main material target is rightly opposite and the adulterant target is eccentric, the graded distribution of the components of the adulterants is realized, and the purpose that the uniaxial anisotropy is obtained is attained. The saturation magnetization (Ms) of the prepared film material is 8 to 25 kG, the equivalent field (Hk) of the uniaxial anisotropy, etc. is 50 to 400 Oe or higher, and the self-resonant frequency is close to 3G Hz or higher.

Disclosed is a semiconductor device which includes a substrate having an air layer or void therein, an interlayer dielectric film above the substrate, and a metal wiring having a spiral structure on the interlayer dielectric film corresponding to or over the air layer. The semiconductor device exhibits reduced parasitic capacitance between the metal wiring (used as an inductor) and the substrate, thereby improving a self-resonance frequency as well as an applicable frequency band of the inductor.

The invention discloses an electric toy car powered by a rail-type wireless power supply system. The electric toy car powered by the rail-type wireless power supply system comprises a transmitter and a receiver which have the same self-resonance frequency, an electric toy car rail is arranged above the area in which a transmitting coil of the transmitter is located, the receiver and a commutating and voltage-stabilizing module are mounted on a chassis of the electric toy car, a receiver is connected to an input end of the commutating and voltage-stabilizing module, and an output end of the commutating and voltage-stabilizing module is connected to an electric motor of the electric toy car. A power source supplies power to the transmitter, the operation of the receiver and the operation of the transmitter are of resonant coupling under the resonant frequency, and energy which is received by the receiver is converted into a voltage-stabilized direct current through the commutating and voltage-stabilizing module and is supplied to the electric motor. The toy car moves on the rail, and the speed of the electric toy car can be adjusted through changes of the power and frequency. By means of the rail-type wireless power supply system, the electric toy car gets rid of the constraint of batteries, the size of the motor is reduced, the weight of a car body is reduced, the conversion efficiency of electric energy is high, pollution to the environment caused by the usage of the storage batteries is reduced, and a good effect in energy conservation and environment protection is achieved.

Although increasing the switching frequency is effective to downsize a power supplying apparatus, the switching loss of a switching element increases if the switching frequency is increased. In a power supplying apparatus including a transformer having a very high boosting ratio, and a plurality of switching elements for supplying AC power to the primary side of the transformer, the frequency of the AC power is set to 0.25 to 2 times the self-resonance frequency of the transformer.

The invention discloses an inductor and a formation method thereof, and an integrated passive device and a formation method thereof. The formation method of the inductor comprises the steps of providing a semiconductor substrate; forming a first medium layer on the semiconductor substrate; forming a metal layer on the first medium layer; forming a mask layer on the metal layer, and forming a first opening and a second opening in the mask layer, wherein the size of the first opening is greater than the size of the second opening; etching the metal layer along the first opening and the second opening until the first medium layer below the first opening is exposed, and leaving the metal layer at predetermined thickness at the bottom of the second opening; removing the mask layer. According to the invention, a quality factor of the inductor in each frequency of an alternating current circuit is improved, the peak value of the quality factor of the inductor is larger, an auto-resonance frequency is larger, and the performance of the integrated passive device comprising the formed inductor is better.

The invention provides paint capable of shielding a chromatic circle inductor and a process for coating the chromatic circle inductor. The paint capable of shielding the chromatic circle inductor is characterized by comprising the following materials in percentage by mass: 25-50% of chromatic circle inductor paint, 20-55% of soft magnetic ferrite magnetic powder, 10-30% of liquid curing agent and 10-30% of diluent; the manufacturing method for the paint capable of shielding the chromatic circle inductor and the process for coating the chromatic circle inductor comprise the steps of coating for two times by using the paint capable of shielding chromatic circle inductor, and then coating for two times by using the paint capable of shielding chromatic circle inductor. The paint capable of shielding the chromatic circle inductor and the process for coating the chromatic circle inductor have the advantages that interference on other parts caused by leakage flux generated in operating of the chromatic circle inductor can be effectively shielded; the cost of the coating can be greatly reduced; the inductance value can be increased; the self-resonance frequency is increased; and the paint is mainly suitable for packaging of the chromatic circle inductor.

The present invention actualizes a drive suited to accummulation, capable of attaining effective drive near the resonance frequency of an oscillating actuator. This drive for oscillating type actuator employs a FLL (Frequency Locked Loop) which detects electromotive force generated at a driving winding by mechanical oscillation during down period of the driving current of an oscillating type actuator, controls oscillating frequency in accordance with the relative time ratio of positive and negative polarities, and draws driving frequency into a section nearer to the self-resonance frequency of the oscillating type actuator.

The present invention provides wireless power transmitting method and apparatus. The wireless power transmitting method according to an embodiment of the present invention may measure a resonance frequency while changing an operating frequency of a resonance circuit, compare the measured resonance frequency with a reference frequency, and wirelessly transmit power when the measured resonance frequency is lower than the reference frequency. The reference frequency may be determined based on two or more among a self resonance frequency of the resonance circuit, a first resonance frequency measured for a receiving device, a second resonance frequency measured for a reference object and a third resonance frequency measured for the receiving device and the reference object.

In accordance with various embodiments, a radio frequency (RF) coil array for use in a magnetic resonance imaging (MRI) system includes at least first and second RF coils. Each of the RF coils have a main body loop configured to at least one of transmit or receive RF energy at an operating imaging frequency in connection with acquiring MRI image data for an MRI system. The RF coil array also includes first and second cables configured to electrically couple the first and second RF coils, respectively, to a system interface. The RF coil array also includes a common ground connection between the first and second cables. The common ground connection is selectively positioned at a grounding point along lengths of the first and second cables to form a ground loop having a select self-resonance frequency (SRF) that differs from the imaging frequency of the MRI system.

The invention provides an inductor component with high inductance and a good DC superposition characteristic. The inductor component can realize high resistance in the high frequency side that is higher than the self-resonance frequency. The inductor component includes a drum core (33) including a winding core portion (32) extending along a longitudinal direction and a pair of flange portions (34,35) disposed on end portions of the winding core portion, a plate core (37) arranged between the pair of flange portions, a wire (38) wound around the winding core portion and a pair of terminal electrodes (39, 40) that are electrically connected to the end portions of the wire. The drum core and the plate core are made of a magnetic material. An average distance (G) between the plate core and the pair of flange portions is no less than about 20 [mu]m and no more than about 50 [mu]m. The wire includes aligned banked winding portions (B1-B4) arranged along the longitudinal direction and more than half of a total number of turns of the wire belong to the aligned banked winding portions (B1-B4).

A small balancer coil for cold-cathode florescent lamps having sufficient shunt/balance effects, comprises a discharge lamp, a conductor located close to the discharge lamp, and two coils whose magnetic fluxes face each other. The magnetic fluxes generated in the coils face and cancel each other. Lamp currents of the discharge lamps are balanced by making the sum of the reactances of the mutual inductance of the balancer coil larger than the negative resistance of the discharge lamp. Section winding is applied to each coil of the balancer coil so as to maintain shunt and balance effects even in a small/flat balancer coil by making self-resonance frequency of each of the coils higher.

The invention discloses a metal button device for a mobile terminal, and a mobile terminal with same. The metal button device comprises a metal triggering detecting device, a resonance matching circuit, a signal generating module and a signal receiving module. The resonance matching circuit is used for matching the metal triggering detecting device and realizing bandpass in a preset frequency. The signal generating module is used for generating a source signal with a preset frequency. The signal receiving module is used for receiving a self-resonance frequency of the metal triggering detecting device and generating a judgment result for judging whether the self-resonance frequency is the preset frequency. Human body triggering causes change of the self-resonance frequency which is generated by the metal triggering detecting device. Based on the change, the signal receiving module can judge whether the triggering detecting device is triggered. Compared with a designing mode of closed-loop power detecting based on an inner complicated circuit design in a chip, change of the self-resonance frequency caused by contact between the human body and the metal triggering detecting device is more obvious. Furthermore a simple, universal and reliable handheld mobile terminal state detection design is realized.

In an antenna coil device 11, a coil portion 12 having a lead wire 2 wound around a magnetic core 1 is mounted on a case 3 made of plastic resin, and on one side of the case 3, terminal boards 4 and 5 that electrically connect one end and the other end of the lead wire 2 of the coil portion 12 to an external device are placed in a protruding manner. A through hole 4D is provided in an inserting end portion 4C of the terminal board 4, a through hole 5H is provided in a central flat portion 5G of the terminal board 5, and the two through holes 4D and 5H are placed opposite each other. This reduces stray capacitance caused between the two terminal boards 4 and 5 connected to both ends of the coil portion 12, and allows a self resonance frequency band where an impedance is equal to or above a predetermined value to be shifted to a high frequency side.

The invention discloses a low-temperature sintering soft magnetic ferrite material and a preparation method thereof, and belongs to the technical field of electronic information functional materials and devices. Iron-nickel-zinc-copper oxide is used as a main component composition, CBS glass is used as a sintering aid, and the low-temperature sintering soft magnetic ferrite material is prepared bya solid-phase reaction method and prepared by ball milling, drying, pre-sintering, secondary ball milling, drying and pulverization and sieving and the other processes. The low-temperature sinteringsoft magnetic ferrite material has the characteristics of low sintering temperature, high self-resonance frequency, high quality factor and high impedance and can be used for manufacturing peak magnetic beads and chip inductors, and the problem that a magnetic body and a silver electrode cannot co-sinter well is solved.

The invention provides a PFC inductor and a variable-frequency air conditioner. The PFC inductor comprises a base, a magnetic core, a separator and a coil, wherein the edge of the magnetic core is fixedly connected with the base; the coil is wound around the magnetic core; the separator is arranged in the diameter of the magnetic core in a direction perpendicular to the base, and is fixedly connected with the magnetic core; fixing parts are arranged on the two sides of the separator, and the two end portions of the coil penetrate through the two fixing parts correspondingly one to one and then are fixed on the base. Due to the adopted structure, the impedance of the PFC inductor is higher than the impedance of two common PFC inductors in the prior art by more than 20%; meanwhile, the self-resonance frequency on the circuit is increased to about 320KHz from the original 270KHz, thereby inhibiting clutter signals generated by the circuit, and therefore, the filtering application effect is improved.

A television signal transmitter has an up-converter provided with a pre-amplifier and an impedance matching circuit subsequent to the pre-amplifier. The self-resonance frequency of an inductor included in the impedance matching circuit, which is connected in series to a signal line, is set to a parasitic oscillation frequency (5 GHz) of the pre-amplifier. The self-resonance frequency of an inductor of a filter provided prior to the pre-amplifier, which is connected in series to the signal line, is set to the parasitic oscillation frequency (5 GHz) of the pre-amplifier.