• Title/Summary/Keyword: Relaxation current

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A Design of 18 MHz Relaxation Oscillator with ±1 % Accuracy Based on Temperature Sensor (Temperature Sensor 기반 ±1 % 이내의 주파수 정확도를 가지는 18 MHz Relaxation Oscillator의 설계)

  • Kim, Sang Yun;Lee, Ju Ri;Lee, Dong Soo;Park, Hyung Gu;Kim, Hong Jin;Lee, Kang-Yoon
    • Journal of Korea Society of Industrial Information Systems
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    • v.18 no.5
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    • pp.39-44
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    • 2013
  • In this paper, a Relaxation Oscillator with temperature compensation using BGR and ADC is presented. The current to determine the frequency of Relaxation Oscillator can be controlled. By adjusting the current according to the temperature using the code that is output from the ADC and BGR, was to compensate the output frequency of the temperature. It is fabricated in a 0.35 ${\mu}m$ CMOS process with an active area of $240{\mu}m{\times}210{\mu}m$. Current consumption is 600 ${\mu}A$ from a 5 V and the rate of change of the output frequency with temperature shows about ${\pm}1%$.

Experimental Investigation of Output Current Variation in Biased Silicon-based Quadrant Photodetector

  • Liu, Hongxu;Wang, Di;Li, Chenang;Jin, Guangyong
    • Current Optics and Photonics
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    • v.4 no.4
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    • pp.273-276
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    • 2020
  • We report on the relationship between output current for quadrant photodetector (QPD) and bias voltage in silicon-based p-i-n (positive-intrinsic-negative) QPD examined using millisecond pulse laser (ms pulse laser) irradiation. The mechanism governing the relationship was further studied experimentally. The output current curves were obtained by carrying out QPD under different bias voltages (0-40 V) irradiated by ms pulse laser. Compared to other photodetectors, the relaxation was created in the output current for QPD which is never present in other photodetectors, such as PIN and avalanche photodetector (APD), and the maximum value of relaxation was from 6.8 to 38.0 ㎂, the amplitude of relaxation increases with bias value. The mechanism behind this relaxation phenomenon can be ascribed to the bias voltage induced Joule heating effect. With bias voltage increasing, the temperature in a QPD device will increase accordingly, which makes carriers in a QPD move more dramatically, and thus leads to the formation of such relaxation.

Dielectric Relaxation Properties of Organic Ultra Thin Films for Nanotechnology (나노기술을 위한 유기초박막의 유전완화특성)

  • Cho, Su-Young;Song, Jin-Won;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.05c
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    • pp.9-13
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    • 2004
  • In this paper, evaluation of physical properties about dielectric relaxation phenomena by the detection of the surface pressures and displacements current on the monolayer films of phospolipid monomolecular DLPC, DMPC using pressure stimulus. As a result, the changed surface pressure, displacement current and the transition forms of dipole moment of phospolipid monomolecular in area per molecular by pressure stimulus were conformed well. It was known that the monolayers by linear relationship for decision of dielectric relaxation time between compressure speed and molecule area By according to the linear relationship relation get that frictional constant, DLPC was $1.89{\times}10^{-19}$[Js] and DMPC was $0.722{\times}10^{-19}$[Js]. It is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area.

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Dielectric Relaxation Characteristics of Biology Thin Film (생체박막의 유전완화특성)

  • Song, Jin-Won;Cho, Su-Young;Lee, Kyung-Sup;Sin, Hun-Gyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05c
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    • pp.107-110
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    • 2003
  • In this paper, We introduced that the method for determing the dielectric relaxation time $\tau$ of floating monolayers on water interface. Displacement current flowing across monolayers is analyzed using a rod-like molecular model. It is revealed that the dielectric relaxation time $\tau$of monolayers in the isotropic polar orientational phase is determined using a linear relationship between the monolayer compression speed $\alpha$ and the molecular area Am. here Displacement current gives a peak at A = Am. The dielectric relaxation time $\tau$ of organic monolayers was examined on the basis of the analysis developed here.

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A study on the Dielectric Relaxation Phenomena of phospolipid monolayers Film (인지질 단분자막의 유전완화현상에 관한 연구)

  • Cho, Su-Young;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.11a
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    • pp.431-434
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    • 2003
  • In this paper, We introduced that the method for deforming the dielectric relaxation time $\tau$ of floating monolayers on water interface. Displacement current flowing across monolayer is analyzed using a rod-like molecular model. It is revealed that the dielectric relaxation time $\tau$ of monolayers in the isotropic polar orientational phase is determined using a linear relashionship between the monolayer compression speed a and the molecular area $A_m$. A displacement current gives a peak at A=$A_m$. The dielectric relaxation time $\tau$ of phospolipid monolayers was examined on the basis of the analysis developed here.

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A Study on Displacement Current DMPC Monolayer (DMPC 단분자막의 변위전류 특성 연구)

  • Choi, Yong-Sung;Cho, Jang-Hoon;Song, Jin-Won;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.168-169
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    • 2006
  • The physical properties of DMPC monolayer were made for dielectric relaxation phenomena by the detection of the surface pressures and displacements current. The phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area.

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The Properties of Na-Ca Exchange Current in Single Atrial Cells of ,The Rabbit (토끼 단일 심방근 세포에서 Na-Ca 교환전류의 특성에 관한 연구)

  • Youm, Wook;Ho, Won-Kyung;Suh, Kyung-Phill
    • Journal of Chest Surgery
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    • v.22 no.4
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    • pp.548-561
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    • 1989
  • In single atrial cells isolated from the rabbit the properties of inward current of Na-Ca exchange were investigated using the whole cell voltage clamp technique. The current was recorded during repolarization following brief 2 ms depolarizing pulse to +40 mV from a holding potential of * 70 mV. Followings are the results obtained: 1. When stimulated every 30 seconds, the inward currents were activated and reached peak values 6-12 ms after the beginning of depolarizing pulse. The mean current amplitude was 342 pA/cell. 2. The current decayed spontaneously from the peak activation and the time course of the relaxation showed two different phases fast and slow phase. The time constants were 10-18 ms and 60-140 ms, respectively. 3. The recovery of inward current was tested by paired pulse of various intervals. The peak current recovered exponentially with time constant of 140 ms and 1 p M isoprenaline accelerated the recovery process. 4. Relaxation time course was also affected by pulse interval and time constant of the fast phase was reduced almost linearly according to the decrease of pulse interval between 30 sec and 1 sec. 5. The peak activation was increased in magnitude by long prepulse stimulation, 5 p M Bay K, 1 p M isoprenaline or internal and external application of c-AMP. 6. The relaxation time constant of the fast phase was prolonged by 5 p M Bay K or c-AMP, and shortened by isoprenaline. However the time course of the slow relaxation phase was not so much changed. From the above results, it could be concluded that increase of the calcium current by Bay K or c-AMP results in the potentiation and prolongation of intracellular calcium transient, and the facilitation of Ca uptake by SR might be a mechanism of shortening the time constant of current relaxation by short interval stimulation or isoprenaline.

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High accuracy, Low Power Spread Spectrum Clock Generator to Reduce EMI for Automotive Applications

  • Lee, Dongsoo;Choi, Jinwook;Oh, Seongjin;Kim, SangYun;Lee, Kang-Yoon
    • IEIE Transactions on Smart Processing and Computing
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    • v.3 no.6
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    • pp.404-409
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    • 2014
  • This paper presents a Spread Spectrum Clock Generator (SSCG) based on Relaxation oscillator using Up/Down Counter. The current is controlled by a counter and the spread spectrum of the Relaxation Oscillator. A Relaxation Oscillator with temperature compensation using the BGR and ADC is presented. The current to determine the frequency of the Relaxation Oscillator can be controlled. The output frequency of the temperature can be compensated by adjusting the current according to the temperature using the code that is the output from the ADC and BGR. EMI Reduction of SSCG is 11 dB, and Spread down frequency is 150 kHz. The current consumption is $600{\mu}A$ from 5V and the operating frequency is from 2.3 MHz to 5.75 MHz. The rate of change of the output frequency with temperature was approximately ${\pm}1%$. The SSCG is fabricated in a 0.35um CMOS process with active area $250um{\times}440um$.

A Study on Elimination Solution of Parasitic Effect to Improve Area Efficiency and Frequency Stability of Relaxation Oscillator (이완 발진기의 면적 효율성과 주파수 안정성 향상을 위한 기생성분 효과 제거 기법연구)

  • Lee, Seung-Woo;Lee, Min-Woong;Kim, Ha-Chul;Cho, Seong-Ik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.4
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    • pp.538-542
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    • 2018
  • In order to generate a clock source with low cost and high performance in system on chip(SoC), a relaxation oscillator with stable output characteristics according to PVT(process, voltage and temperature) fluctuation require a low area and a low power. In this paper, we propose a solution to reduce the current loss caused by parasitic components in the conventional relaxation oscillator. Since the slew rate of the bias current and the capacitor are adjusted to be the same through the proposed solution, a relaxation oscillator with low area characteristics is designed for the same clock source frequency implementation. The proposed circuit is designed using the TSMC CMOS 0.18um process. The Simulation results show that the relaxation oscillator using the proposed solution can prevent the current loss of about $279{\mu}A$ and reduce the total chip area by 20.8% compared with the conventional oscillator in the clock source frequency of 96 MHz.

Dielectric Relaxation Characteristics of Phospholipid Membrane (인지질막의 유전완화 특성)

  • 이경섭;조수영;박석순;정헌상;최영일
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.06a
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    • pp.173-176
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    • 1998
  • We experimentally investigated the dielectric relaxation phenomena of a liquid crystal monolayers by the Displacement current techique and displacement current flowing across monolayers is analyzed using rod-like molecular model. It is revealed that the dielectric reaxation time $\tau$ of monolaters in the isotropic polar orientational phase is determined using a linear relashionship between the monolayers compression speed $\alpha$ and the molecular area. The dielectric relaxation time of phospholipid monolayers was examined on the basis of the analysis developed here.

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