• Journal of Power Electronics
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• v.13 no.6
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• pp.991-999
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• 2013

In this paper, a fast transient buck converter using hysteresis PWM control is presented. The proposed control method is based on hysteresis control of the capacitor C voltage. This offers a faster transient response to meet the challenges of the power supply requirements for fast dynamic input and load changes. It also provides better stability and solves the compensation problem of the error amplifier in conversional voltage PWM control. Finally, the steady-state and dynamic operation of the proposed control method are analyzed and verified by simulation and experimental results.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.609-614
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• 2014

The fringe field effects on the transient characteristics of nano-electromechanical (NEM) memory cells have been discussed by using an analytical model. The influence of fringe field becomes stronger as the size of a cell decreases. By using the proposed model, the dependency of NEM memory transient characteristics on cell parameters has been evaluated.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.2
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• pp.63-68
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• 2009

We study on the transient response in non-uniform microstrip lines with optically controlled microwave pulses. The transient response of the microwave pulses in plasma layer has been evaluated by reflection function of dielectric microstrip lines. The variation of characteristic response in plasma layer with localized pulses has been evaluated analytically. Reflection the change of the reflection amplitude has been observed.

• Journal of IKEEE
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• v.20 no.3
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• pp.314-317
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• 2016

Recently, efforts to maximize battery life in progress with an increase in the demand for portable devices. In this paper, we propose multi-phase buck converter with fast transient response. Multi-phase buck converter may be used for the output capacitor of small size because the ripple cancellation effect, it is possible to use an inductor having an inductance less. The portable device for quick change from standby mode to active 4-phase design structure was given a fast transient response. The proposed multi-phase buck converter was fabricated using a 0.18 um CMOS process and the supply voltage ranges from 2.7V to 3.3V, the maximum load current is 500mA and settling time is 10us.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.9
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• pp.35-41
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• 1998

A transient chirp measurement was used to analyze the chirping characteristics of modulator integrated DFB (MI-DFB) laser module. This method measures the wavelength change due to a small variation in modulation with bias. The measurement system includes a monochrometer and digitizing oscilloscope. The chirping characteristics due to packaging influences can also be accounted for. The chirp parameter calculated using this method was compared with the peak-to peak chirp. They showed the same tendency with modulator bias voltage. These results can be used as a reference when optimizing system parameters.

• Journal of Power Electronics
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• v.16 no.6
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• pp.2327-2337
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• 2016

The mode-switching control of transient process is important to grid-connected 400 Hz solid-state power supply systems. Therefore, this paper analyzes the principle of on-grid and islanding operation of the system with or without local loads in the grid-connected process and provides a theoretical study of the effect of different switching sequences on the mode-switching transient process. The conclusion is that the mode switch (MS) must be turned on before the solid-state switch (STS) in the on-grid process and that STS must be turned off before the MS in the off-grid process. A strategy of mode-switching smooth control for transient process of the system is proposed, including its concrete steps. The strategy utilizes the average distribution of peak currents and the smooth adjustment of peak currents and phases to achieve a no-shock grid connection. The simulation and experimental results show that the theoretical analysis is correct and that the method is effective.

• Journal of IKEEE
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• v.25 no.1
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• pp.201-205
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• 2021

In this paper present Low Drop-Out (LDO) regulator that improved load transient characteristics due to the push-pull detection structure. The response characteristic of the voltage delta value is improved due to the proposed push-pull sensing circuit structure between the input terminal of the LDO regulator pass transistor and the output terminal of the internal error amplifier. Voltage value has improved load transient characteristics than conventional LDO regulator. Compared to the conventional LDO regulator, it has an improved response speed of approximately 244 ns at rising time and approximately 90 ns at falling time. The proposed circuit was simulated by the samsung 0.13um process using Cadence's Specter and Virtuoso simulator.

• Journal of IKEEE
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• v.20 no.3
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• pp.307-309
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• 2016

In this paper, we propose LDO regulator with improved transient using a simple feedback structure in conventional LDO regulator. This proposed circuit has the feedback structure which reduces the response time of overshoot appeared in the output of conventional LDO regulator. Therefore, this LDO regulator can be a more stable operation. Thus, the proposed feedback structure is to operate such as conventional LDO regulator without changing the area, it complements the disadvantage of LDO regulator with noise in the output. This circuit was designed to using a Dongbu Hitek 0.18um CMOS process.

• Journal of Power Electronics
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• v.3 no.4
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• pp.230-238
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• 2003

Electric vehicles (EV) demands for greater acceleration, performance and vehicle range in pure electric vehicles plus mandated requirements to further reduce emissions in hybrid electric vehicles (HEV) increase the appeal for combined on-board energy storage systems and generators. And the power electronics plays an important role in providing an interface between fuel cells (FC) and loads. This paper deals with a multiple input DC-DC power converter devoted to combine the power flowing of multi-source on energy systems. The multi-source is composed of (i) FC system as a prime power demands, (ii) super capacitor banks as energy storage devices for high and intense power demands, (iii) superconducting magnetic energy storage system (SMES), (iv) multiple input DC-DC power converter and (v) a three phase inverter-fed permanent magnet synchronous motor as a drive. In this system, It is used super capacitor banks and superconducting magnetic energy replaces from the battery system. The modeling and transient performance simulation is effective for reducing transient influence caused by sudden charge of effective load. The main purpose of power electronic converters is to convert the DC power output from the fuel cell and other to a suitable AC voltage, which can be connected to electric loads directly (PMSM). The fuel cell and other output is connected to the DC-DC converter, which regulates the DC link voltage.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.1
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• pp.66-71
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• 1998

Discretization method and numerical calculations of wigner function to introduce the influence of spatially varying effective mass as well as to reduce the error involved in the conventional discretization model are presented. Using this new discrete model, the transient responses of resonant-tunneling-diode are analyzed.