• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.605-608
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• 2002

This paper proposes a real-time wall charge measurement circuit for three-electrode AC PDP. It includes a charge-compensation network, current-integrating capacitors, initializing switches, and an op-amp. With this equipment, we measure the wall charge variations for the effects of sustain voltage, sustain pulse width, sustain frequency, and neighboring cells.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.581-584
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• 2003

The phase differences and noise signals are in general serious on output of a instrumentation amplifier for signal conditioning of a sensor driven at high frequency due to a time-varying input signal. In this study, we get the better amplification and S/N ratio using the rectified signal for the input of instrumentation amplifier. This driving circuits were designed and constructed by OrCAD and laboratory PCB process. All of the elements used on the circuit including highly speedy OP-Amp. was SMD type and the MI sensor was fabricated by meander-patterned amorphous ribbon. The output sensitivity of this circuit was $105.3mV/V{\cdot}Oe$. That's why this driving circuit is good at detection of fine magnetic field.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.1
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• pp.311-316
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• 2012

In this paper, chaotic circuit of the Lorentz system for engineering applications was implemented using resistor, multipliers, capacitors and operational amplifiers. The implemented Lorentz chaotic system was analysed by PSPICE program. PSPICE simulation results show many kind of chaotic phenomena such time waveforms and phase plots. Meanwhile, according to resistor's variation, we got that Lorentz system show equilibrium state, periodic state and chaotic state.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.1
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• pp.59-62
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• 2014

Glucose uptake plays a pivotal role in maintaining whole body glucose homeostasis in adipocytes and skeletal muscles. In the present study we have shown that Fructus Piperis Longi Extracts (FPLE) can stimulate glucose uptake in OP9 adipocytes. The increasing effects of FPLE on glucose uptake were inhibited by compound C pretreatment, which means that the glucose uptake effects by FPLE were carried out by AMP-activated protein kinase (AMPK) activation. Further studies revealed that FPLE stimulated glucose transport occurs through a mechanism involving extracellular signal-regulated kinase (ERK1/2) activation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.383-388
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• 1995

The ARC light has been measured using photo-detect system under different TIG welding condition. Light detect system consists of photo diode, ND Filter, OP Amp. A/D convertor and PC. The purpose of this experiment is to show the relationship between ARC light and process variables such as welding current, torch travel speed, etc. The results can be applied to estimate the condition of welding process and the quality of welding products. The signal of ARC light has periodic patterns in good TIG welding condition whereas in abnormal condition the signal has different pattern. Amount of Ar shielding gas and distance from electrode to specimen affect the signal pattern significantly.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.7
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• pp.1579-1589
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• 1997

This paper introduces a monolithic chip 3.3V high-performance continuous-tune filter used in a CDP that can reconstruct the PDM or PWM signal output of a .SIGMA..DELTA. D/A converter. We also mentioned an active RC filter structure and filter order satisfying high-linearity and the design specification. In desigining the OP-AMP, using a structure that accepts some distortion we could reduce the chip area, and reducing the DC path using a new biascircuit gave us better power performance. The designed.SIGMA..DELTA. D/A converter post-processing filter does its smoothering operations and reconstructs the data without reducing the performance of the system.

• Journal of the Korea Society of Computer and Information
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• v.7 no.2
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• pp.68-72
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• 2002

In this study, I studied on the principle of OTA and it's basic application. Here, I designed second order filter using OTA. This filter has three inputs and one output. If we use each one input among them, we can get a low pass, high pass and band pass output. In the result of the computer simulation. the linear characteristics was superior to the conventional Op-Amp filter. And this circuit is advantageous to making an IC. This will be used to the communication system which has the low distortion and high frequency circuit. This study will have to be continued to form a higher order filter using OTA.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.2
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• pp.102-108
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• 2001

In this paper, an active noise controller for a communication headset was designed. In a communication headset, there exist information signals such as voices from the end for the communication line as well as also, undesirable noises with are induced by external noise sources such as engine noises. Therefore, it is necessary to reduce the external noises for clear hearing of the communication signals. This problem was solved by robust H(sub)$\infty$ controller to reduce noise and a compensator for information signals The designed controller was implemented using TMS320C31 DSP Op-amp, and several experiments were performed to verify its performance. The results showed that the controller reduces the undesirable noises sufficiently, while communication signals are not reduced.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.627-628
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• 2006

A low-voltage switched-capacitor $2^{nd}$-order $\Sigma\Delta$ modulator using full feed-forward is introduced. It has two advantages: the unity signal transfer function and reduced signal swings inside the $\Sigma\Delta$ loop. These features greatly relax the DC gain and output swing requirements for Op-Amp in the low-voltage $\Sigma\Delta$ modulator. Implemented by a 0.18-${\mu}m$ CMOS technology, the $\Sigma\Delta$ modulator satisfies performance requirements for WCDMA and CDMA2000 standards.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.3
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• pp.319-329
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• 2016

High-level design aids are mandatory for design of a continuous-time delta-sigma modulator (CTDSM). This paper proposes a top-down methodology design to generate a noise transfer function (NTF) which is compensated for excess loop delay (ELD). This method is applicable to low pass loop-filter topologies. Non-ideal effects including ELD, integrator scaling issue, finite op-amp performance, clock jitter and DAC inaccuracies are explicitly represented in a behavioral simulation of a CTDSM. Mathematical modeling using MATLAB is supplemented with circuit-level simulation using Verilog-A blocks. Behavioral simulation and circuit-level simulation using Verilog-A blocks are used to validate our approach.