Showing papers on "RLC circuit published in 2001"

Design and application of a wireless, passive, resonant-circuit environmental monitoring sensor

Abstract: A wireless, passive, remote query sensor platform is presented capable of monitoring the complex permittivity of a surrounding medium, temperature, humidity, and pressure. The sensor is a planar two-dimensional inductor–capacitor circuit, of scaleable-size, that resonates at a characteristic frequency the value of which is dependent upon the parameters of interest. The resonant frequency of the sensor is detected remotely with one or a pair of loop antennas by measuring the impedance or voltage spectrum of the antenna(s), with the environmental parameters of interest then calculated from the measured resonant frequency. The wireless, remote query nature of the platform enables the LC sensor to monitor the environmental conditions from within sealed opaque containers. The paper describes the operational principles, design criteria, illustrative applications, and performance limitations of the sensor platform.

A critical analysis of electric shunt circuits employed in piezoelectric passive vibration damping

Abstract: Vibration damping of an elastic structure can be obtained by bonding a piezoelectric actuator onto the vibrating structure, and by shunting the actuator to a suitable electric resonant circuit, tuned to the structural eigenmode to be damped. The achievable damping depends on the particular electric circuit used. In this paper three different electric shunt circuits are analyzed and their performances are compared. In particular, the optimal values of the electric components belonging to each shunt circuit and the corresponding exponential time decay rates of the free vibrations relevant to the controlled structural eigenmode are explicitly determined, also taking into account the inherent structural damping. Finally, some experimental results are reported, obtained by using two of the shunt circuits analyzed, which are in good agreement with the theoretical predictions.

Power plane SPICE models and simulated performance for materials and geometries

Abstract: A SPICE model for power plane simulation has been developed. It is based on the geometries and materials of the power planes and uses a unit cell composed of RLC elements, transmission line elements or the HSPICE W-element. Simulated resonances in the frequency domain and delays in the time domain are consistent with results calculated from physical dimensions. SPICE model simulations compare well with hardware measurements in both the frequency and time domains. The role of dielectric thickness, dielectric constant and parallel pairs of power planes is demonstrated through simulation. The spreading inductance of power planes is defined, discussed and measured. Power plane performance in terms of impedance, resonances, damping and spreading inductance is optimized by the use of a thin dielectric layer between conductive planes.

X-ray computer tomography apparatus

Abstract: An X-ray computer tomography apparatus comprises a high-voltage transformer which performs the increase and noncontacting transmission of the power simultaneously and outputs a desired high voltage for causing X rays to be generated at the rotatable gantry section. The high-voltage transformer is divided into a primary-side which is provided on the static gantry section and to which the output of a frequency converting circuit is supplied and a secondary-side which generates a high voltage. A capacitor is connected to a secondary coil of the high-voltage transformer, thereby forming a resonance circuit.

Method for transmitting data from RLC layer in radio communication system

Abstract: Disclosed is a method for transmitting data from an RLC layer in a radio communication system The method includes the steps of storing RLC SDUs transferred from an upper layer in a transmission buffer, transmitting RLC PDUs on which the RLC SDUs stored in the transmission buffer are loaded to a receiving side in order, discarding the RLC SDUs stored in the transmission buffer, checking whether a transmission mode indicator is configured, and transmitting discard information about the discarded RLC SDUs to the receiving side entirely or in part in accordance with whether the transmission MRW mode indicator is configured

Inductor-less piezoelectric transformer electronic ballast for linear fluorescent lamp

Abstract: This paper presents a cost-effective piezoelectric transformer based ballast circuit that is designed to drive a linear fluorescent lamp without dependence on any magnetic devices. This innovative circuit uses a radial vibration mode piezoelectric transformer or Transoner(R) to replace the inductor and the capacitors of the resonant tank portion in conventional electronic ballast circuits in order to effectively reduce the component number and cost. By fully utilizing the characteristics of the radial vibration mode piezoelectric transformer, the switches of the ballast circuit can work in a ZVS (zero-voltage switching) condition thus significantly reducing the turn-on switching losses when compared to a hard-switching topology. In addition, the inherent input capacitance of the radial vibration mode piezoelectric transformer enhances circuit operation by serving as a turn-off snubber for the half-bridge switches. This decreases turn-off voltage spiking thus reducing the turn-off losses for the half-bridge switches of the proposed circuit. Through these innovative circuit techniques, the proposed circuit provided 32-watts of power at commendable efficiency of around 90% when utilizing a standard 110-volt 60-Hz line as the power source and a 4-foot 40-watt linear fluorescent lamp as a load.

Accurate analysis of on-chip inductance effects and implications for optimal repeater insertion and technology scaling

Abstract: This paper introduces an accurate analysis of on-chip inductance effects for distributed RLC interconnects that takes the effect of both the series resistance and the output parasitic capacitance of the driver into account Using rigorous first principle calculations, accurate expressions for the transfer function of these lines and their time-domain response have been presented for the first time Furthermore, an optimal repeater insertion scheme for distributed RLC interconnects is also presented using a novel performance optimization methodology Additionally, the impact of line inductance on interconnect performance has been analyzed in detail with particular regards to technology scaling based on the International Technology Roadmap for Semiconductors (ITRS) Contrary to conventional wisdom, it is shown that the effect of line inductance on optimized interconnect performance will actually diminish for scaled global interconnects

On-Chip Inductance in High Speed Integrated Circuits

Abstract: List of Figures. List of Tables. Preface. 1. Introduction. 2. Basic Transmission Line Theory. 3. Evaluating the Transient Response of Linear Networks. 4. Mosfet Current-Voltage Characteristics. 5. Figures of Merit to Characterize the Importance of on-Chip Inductance in Single Lines. 6. Effects of Inductance on the Propagation Delay and Repeater Insertion Process in RLC Lines. 7. Equivalent Elmore Delay for RLC Trees. 8. Characterizing Inductance Effects in RLC Trees. 9. Repeater Insertion in Tree Structured Inductive Interconnect. 10. Dynamic and Short-Circuit Power of CMOS Gates Driving Lossless Transmission Lines. 11. Exploiting On-Chip Inductance in High Speed Clock Distribution Networks. 12. Accurate and Efficient Evaluation of the Transient Response in RLC Circuits: The DTT Method. 13. On the Extraction of On-Chip Inductance. 14. Conclusions. Bibliography. Appendices. Index. About the Authors.

Electrode structure of tag for rfid and method for adjusting resonance frequency using the same electrode

Abstract: PROBLEM TO BE SOLVED: To provide an electrode structure of a tag for RFID (radio frequency identification) by which a resonance frequency of a resonant circuit to be formed on the tag for RFID can be easily adjusted after formation of the circuit and a method for adjusting the resonance frequency using the electrode. SOLUTION: In an RFID system for communicating data between a reader/ writer and the tag by using electromagnetic induction, a comb-line electrode 7 of a capacitor constituting the resonant circuit of the tag and a counter electrode 8 to be formed on the opposite side by sandwiching a substrate are formed so that area of an overlapped part between each finger 7b of the comb-line electrode 7 and the counter electrode 8 gradually becomes small from the tip side to the root side of the comb-line electrode 7, for example, the counter electrode 8 is formed like a taper and shift quantity of the resonance frequency when the fingers 7b are successively cut off is set as approximately equivalent values. Thus, the number of fingers to be cut off is directly determined from the shift quantity from desired resonant frequency and an adjustment work of the resonant frequency is facilitated. COPYRIGHT: (C)2003,JPO

Model reduction of variable-geometry interconnects using variational spectrally-weighted balanced truncation

Abstract: This paper presents a spectrally-weighted balanced truncation technique for RLC interconnects, a technique needed when the interconnect circuit parameters change as a result of variations in the manufacturing process. The salient features of this algorithm are the inclusion of parameter variations in the RLC interconnect, the guaranteed stability of the reduced transfer function, and the availability of provable frequency-weighted error bounds for the reduced-order system. This paper shows that the balanced truncation technique is an effective model-order reduction technique when variations in the circuit parameters are taken into consideration. Experimental results show that the new variational spectrally-weighted balanced truncation attains, on average, 20% more accuracy than the variational Krylov-subspace-based model-order reduction techniques while the run-time is also, on average, 5% faster.

Switching power supply apparatus with active clamp circuit

Abstract: An active clamp circuit is provided on the primary side of a complex resonance type switching converter having a voltage resonance type converter on the primary side and a parallel resonant circuit on the secondary side. The active clamp circuit clamps a parallel resonance voltage pulse generated across a primary-side parallel resonant capacitor to thereby suppress the level of the parallel resonance voltage pulse. Thus, products having low withstand voltage may be selected for components such as switching devices and the primary-side parallel resonant capacitor provided in the power supply circuit. An auxiliary switching device Q2 of the active clamp circuit is driven by a self-oscillation circuit formed by winding a wire of the primary winding of an insulating converter transformer by 1T. Thus, the circuit system for driving the active clamp circuit is simplified, thereby improving power conversion efficiency and miniaturizing the power supply circuit.

Method for regulating and/or controlling a welding current source with a resonance circuit

Abstract: The invention relates to a method for regulating a welding current source (2) with a resonance circuit (27). According to said method, a bridge circuit (28) is driven through a control device (4). A consumer, especially a welding process, is supplied with energy from an energy source (29) through said bridge circuit (28). Said predetermined switching states (S1 to S6) are stored for driving the individual switching elements (32 to 35) of the bridge circuit (28). When the control device is in its normal operating mode, the bridge circuit (28) is driven according to the switching states (S1 to S4) in succession. In the event of a change in resistance on the consumer side, the control device (5) executes a special operating mode with the resonance frequency of the resonance circuit (27) and drives the bridge circuit (28) according to the switching state provided for the special operating mode.

Method and apparatus for synthesizing high-frequency signals for wireless communications

Abstract: A frequency synthesizer is provided with a prescaler 2 and a counter 3, which output a signal having a frequency generated by frequency-dividing an output signal of a VCO 1; a reference frequency divider 5 for frequency-dividing a frequency of a reference signal of a reference signal source 4; a frequency adjusting meas 9 operated in such that a frequency error between the output signal of the counter 5 and the output signal of the reference frequency divider 5 is detected, and in response to this detection result, such a signal is outputted by which either a capacitor value or an inductor value employed in a resonant circuit of the VCO 1 is switched; and also a bias control means for applying an arbitrary voltage V1 to a control voltage terminal of the VCO 1 so as to bring an output signal of a charge pump 7 into a high impedance state when the frequency adjusting means 9 is operated. Since the resonant frequency of the resonant circuit is changed in response to an actual oscillation frequency of the VCO 1, the frequency synthesizer can be phase-locked at a desirable frequency. Also, since the VCO can be manufactured in the IC form, the compact VCO can be made in low cost.

An improved zero-voltage and zero-current-switching full-bridge PWM converter using a simple resonant circuit

Abstract: An improved zero-voltage and zero-current-witching full-bridge pulsewidth modulation (ZVZCS-FB-PWM) DC-to-DC converter is presented and analyzed. An auxiliary resonant circuit, which consists of a switch and a capacitor, are added to provide zero-current switching (ZCS) conditions to the primary lagging-leg switches. Due to the auxiliary circuit, when the primary current is being extinguished, the voltage applied on the leakage inductance of the transformer is larger than DC-link voltage. This large voltage increases the maximal output current that can be handled in ZCS. Furthermore, the auxiliary switch softly turns on and turns off.

Non-contact identification medium

Abstract: PROBLEM TO BE SOLVED: To directly give influence on a resonance frequency caused by manufacturing variation of capacity between IC terminals in a RFID having a resonance circuit; to dispense with a process compensating this manufacturing variation even though directly giving influence on receiving efficiency of electric power and a communication distance; to reduce manufacturing costs; and to effectively receive electric power. SOLUTION: A condenser 5 is connected with the IC 3 in series through an middle tap 2 of an antenna coil 1 so that capacity between terminals of an IC 3 has less influence on the resonance frequency, or the condenser 5 is connected with the IC in series by dividing the condenser 5. COPYRIGHT: (C)2005,JPO&NCIPI

Multiphase zero-volt-switching resonant DC-DC regulator

Abstract: A multiphase zero-volt switching, zero volt switch resonant DC-DC regulator includes: a zero-volt switch zero volt switch; a DC output voltage means; a variable resonant circuit; a synchronous rectifier; and a sensing circuit. The sensing circuit senses a DC output voltage at the DC output of the regulator. The regulator uses the resonant circuit in conjunction with the sensing circuit to provide a substantially constant DC output voltage at a fixed frequency. If the sensing circuit senses a change in the DC output voltage, then a resonant frequency of the regulator is changed by the variable resonant circuit. This allows the oscillator of the regulator to maintain a fixed frequency, thus ensuring the availability of zero-volt switching over the full range of operation. The regulator also has the advantages of low power loss, reduced ripple, and a very fast transient response time.

Complex resonant DC-DC converter and high voltage generating circuit driven in a plurality of frequency regions

Abstract: A DC-DC converter includes a switching unit having a pair of switching devices or transistors, a resonant circuit comprising a capacitor, an inductor, and a primary coil of a converter transformer which serves as an inductor, a smoothing and rectifying circuit connected to a load in the secondary, an error amplifier for the output voltage, and a variable oscillator for varying the switching frequency according to the error voltage. The output of the variable oscillator circuit is supplied to the switching devices to provide a stabilized output voltage from the smoothing and rectifying circuit. The switching frequency during light loading is set at a frequency more than the resonant frequency which is mainly defined by the inductance and the interwinding capacitance of the secondary coil. The switching frequency to stabilize the output voltage during light loading is much higher than that during heavy loading, significantly reducing the exciting current component during light loading to enhance the energy conversion efficiency during light loading.

High frequency model for power electronics capacitors

Abstract: The study of metallized capacitor behavior at high frequencies points out the presence of series and parallel resonances that could lead to oscillations, perturbations and additional losses in power electronics apparatus. Starting from an already established analytical model of this resonance, we propose a method to elaborate equivalent circuits suiting circuit simulators. These models should help further investigations on high frequency properties of decoupling and snubber capacitors in commutation cells.

Human body detector

Abstract: In a human body detector, a wave-detection circuit for detecting waves of a resonance voltage is connected to a sensor resonance circuit that varies a constant frequency voltage in accordance with a change in the capacitance of a sensor electrode. The wave-detection circuit is connected to a differentiator that acquires a changing rate by differentiating the wave-detection voltage with respect to time, and allows a voltage to pass if the changing rate of the voltage is greater than or equal to a predetermined value. The differentiator is connected to a high-pass filter that allows passage of a voltage whose changing rate is greater than or equal to a second predetermined value. The high-pass filter is connected to a comparator whose non-inversion input terminal is connected to a power source that applies thereto a reference voltage.

Impedance matching circuit and antenna apparatus using the same

Abstract: One matching circuit ( 8 - 2 ) comprises a transmission line ( 6 b ) of a predetermined electrical length and a parallel resonance circuit ( 5 ) connected in parallel with the transmission line. The resonance circuit has a resonant frequency f 2 and a predetermined susceptance at a frequency f 1 lower than the frequency f 2 . ANother matching circuit ( 8 - 1 ) comprises a transmission line ( 6 a ) of a predetermined electrical length and a capacitor element (b 3 a ) connected in series with the transmission line between an input terminal ( 2 ) of an antenna ( 1 ) and the matching circuit ( 8 - 2 ) so that the input impedence of the antenna at the frequency f 2 may match the characteristic impedance of an external circuit ( 10 ).

Integrated power oscillator RF source for plasma immersion ion implantation system

Abstract: A wafer processing system is provided. The system includes a wafer handling system for introducing semiconductor wafers into a processing chamber (20). An oscillator (80) is operatively coupled to an antenna (30a) for igniting a plasma (94) within the processing chamber (20). The plasma (94) and antenna (30a) form a resonant circuit (90a) with the oscillator (80), and the oscillator (80) varies an output characteristic associated therewith based on a load change in the resonant circuit during plasma ignition.

Distributed SPICE circuit model for ceramic capacitors

Abstract: Discrete ceramic capacitors are used to achieve a low power supply impedance in the MHz range. The traditional series RLC circuit model for discrete capacitors is inadequate for low ESR capacitors when mounted on low ESL pads. When combined with other capacitors or power plane models, the simple RLC model does not correctly predict the magnitude or frequency of the anti-resonant peak formed by the parallel components. Discrete capacitors have higher ESR and lower inductance than expected at frequencies above series resonance. A new distributed circuit model is proposed for high Q, low ESR capacitors. The distributed model correlates well with hardware measurements. Both simulated and measured results indicate that anti-resonant peaks are higher in frequency and lower in magnitude than predicted by the traditional series RLC model. Low ESR capacitors do not create the high impedance peak expected from simulation of the traditional series RLC circuit model.

Precision oscillator circuits and methods with switched capacitor frequency control and frequency-setting resistor

Abstract: A precision oscillator circuit providing a periodic waveform is provided. A periodic waveform is provided by the use of an integrating op-amp circuit in conjunction with a switched capacitor frequency control loop and a user input adapted to be coupled with a frequency-setting resistor. The frequency of the periodic waveform is determined by the values of the switched capacitor and the resistor. The oscillator circuit has an arrangement which minimizes the effect of the op-amp circuit's offset voltage. The user input is kept robust against user-introduced capacitance by the use of controllable current sources and/or controllable voltage sources to bias the op-amp circuit. A linearity correction circuit is also provided to correct for non-ideal op-amp circuits.

Antenna device and portable radio system

Abstract: PROBLEM TO BE SOLVED: To provide an antenna device for obtaining a wide band width in a plurality of frequency bands. SOLUTION: A part of a reverse-F antenna element made up of a flat element 1 and a flat element 2 is connected electrically through a short-circuiting part 3 to a grounding plate 6. A series resonance circuit 9 made up of inductance 7 and a capacitor 8 connected in series and a serial resonance circuit 12 made up of inductance 10 and a capacitor 11 connected in series are connected in parallel with a power feed unit 4. The other end of the parallel connection of the series resonance circuits 9 and 12 is connected to the power feed terminal 13, and the radio circuit is fed with power through the power feed terminal 13. COPYRIGHT: (C)2003,JPO

Repeater insertion in tree structured inductive interconnect

Abstract: The effects of inductance on repeater insertion in RLC trees is the focus of this paper. An algorithm is introduced to insert and size repeaters within an RLC tree to optimize a variety of possible cost functions such as minimizing the maximum path delay, the skew between branches, or a combination of area, power, and delay. The algorithm has a complexity proportional to the square of the number of possible repeater positions and determines a repeater solution that is close to the global minimum. The repeater insertion algorithm is used to insert repeaters within several copper-based interconnect trees to minimize the maximum path delay based on both an RC model and an RLC model. The two buffering solutions are compared using the AS/X dynamic circuit simulator. It is shown that as inductance effects increase, the area and power consumed by the inserted repeaters to minimize the path delays of an RLC tree decreases. By including inductance in the repeater insertion methodology, the interconnect is modeled more accurately as compared to an RC model, permitting average savings in area, power, and delay of 40.8%, 15.6%, and 6.7%, respectively, for a variety of copper-based interconnect trees from a 0.25 /spl mu/m CMOS technology. The average savings in area, power, and delay increases to 62.2%, 57.2%, and 9.4%, respectively, when using five times faster devices with the same interconnect trees.

Superconducting control elements for RF antennas

Abstract: Control elements for RF antennas including high temperature superconducting capacitors, alone or in combination with other elements, including high temperature superconducting films, structures, and applications are formed In one embodiment a high temperature superconducting capacitor is coupled to an inductor to form a resonant circuit In another embodiment a high temperature superconducting capacitor is used to make a low-resistance cross-over for an inductor coil Additional circuits include circuits which do not use non-superconducting materials in the circuit, circuits which have coupled superconducting inductors to provide low-loss signal coupling, tuning and bandwidth broadening, and circuits which include switches to shut off the superconductivity of a superconducting element including low-loss photoconducting and superconducting thermal switches These circuits may be used to improve Magnetic Resonance Imaging (MRI)

Method and system for driving a capacitively coupled fluorescent lamp

Abstract: A capacitively coupled fluorescent lamp package having a capacitively coupled fluorescent lamp; an inverter circuit for driving the lamp; and supply nodes for receiving a supply voltage is disclosed. The capacitively coupled fluorescent lamp package includes a resonant circuit lamp driving scheme for driving the capacitively coupled fluorescent lamp. The driving scheme reduces parasitic capacitance leakage current; compensates the reactive power using the secondary side leakage inductance in order to have the resonant frequency approximately equal the inverter circuit operating frequency for current source-type driven circuits; and forms a series resonant sub-circuit with the embedded ballasting capacitor and the secondary side leakage inductance for voltage source-type driven circuits, such that the resonant frequency is substantially less than the inverter circuit operating frequency and that the lamp current is properly shaped along with current ballasting.

Multifrequency antenna for instrument with small volume

Abstract: The invention concerns an antenna (1) consisting of a first strip (3) whereof the length (L1) is tuned at a high frequency (fh) and a second strip (4), extending the first of length (L2). The sum of lengths L1 and L2 results into an antenna whereof the length L3 is tuned at a low frequency (fb). A resonant circuit (5) comprising an inductance (6), connected in parallel on a capacitor (7) is located between the first and second strips (3, 4). The values of said components are selected so as to cause the resonant circuit to resonate on the high frequency (fh). When the high frequency is active, the length of the antenna is reduced to that (L1) of the first strip. When the low frequency is active, the length of the antenna extends to the sum (L3) of the lengths provided by the first and second strips. The inductance (6) is a narrow strip substantially rectilinear formed integrally with at least (3) one of said strips linked to said strip (8) by one of its ends.

Multi-channel RF cable trap for magnetic resonance apparatus

Abstract: A multi-channel RF cable trap (70) blocks stray RF current from flowing on shield conductors (114) of coaxial RF cables (60) of a magnetic resonance apparatus. An inductor (116) is formed by a curved semi-rigid trough (80) constructed of an insulating material coated with an electrically conducting layer. Preferably, the inductor (116) and the cable follow an 'S'-shaped path to facilitate good electromagnetic coupling therebetween. The RF cables (60) are laid in the trough (80) and the shield conductors inductively couple with the inductor (116). A capacitor (82) and optional trim capacitor (83) are connected across the trough of the inductor (116) to form a resonant LC circuit tuned to the resonance frequency. The LC circuit inductively couples with the shield conductors (114) to present a high, signal attenuating impedance at the resonance frequency. The resonant circuit is preferably contained in an RF-shielding box (84) with removable lid.

High frequency DC to AC inverter

Abstract: A high-frequency resonant sine wave DC to AC inverter suitable for use in a personal computer (PC) power supply includes a full-bridge inverter, a resonant circuit, a phase shift modulation circuit, and a resonant gate driver. The resonant gate driver provides sinusoidal gate drive signals to the full-bridge inverter enabling highly efficient operation on the inverter.