• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.2 s.105
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• pp.129-133
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• 2006

In spite of the advantage of simple circuit, small size, and low price, predistortered power amplifier does not satisfy the IMD specification at low power range because of an IMD hump characteristic. To reduce the performance degradation by IMD hump, the method which is to control the operating point of amplifier according to its output power is presented. This method using envelope detection bias control is applied to the implemented class AB predistortered 16 W power amplifier. The measured result shows 10 dB improvement of $3^{rd}$ IMD performance in wide dynamic range of output power.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.213-216
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• 2008

The voltages for pixel electrodes on LCD panels are supplied with analog voltages from LCD Driver ICs (LDIs). The latest LDI developed for large LCD TV's has suffered from the degradation of analog output characteristics (target voltage: AVO and output voltage deviation: dVO). By the failure analysis, humps in $I_D-V_G$ curves have been observed in high voltage (HV) NMOS devices for input transistors in amplifiers. The hump is investigated to be the main cause of the deviation for the driving current in HV NMOS transistors. It also makes the matching between two input transistors worse and consequently aggravates the analog output characteristics. By simply modifying the active layout of HV NMOS transistors, this hump was removed and the analog characteristics (AVO &dVO) were improved significantly. In the help of the improved analog characteristics, it also became possible to reduce the size of the input transistors less than a half of conventional transistors and significantly improve the integration density of LDIs.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.1
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• pp.155-159
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• 2009

To increase the luminance and luminous efficacy in the discharge for alternating current plasma display panel (ac PDP), the increment of Xe contents and long discharge gap are necessary. However, the driving voltage and the cost of driving circuit increases in the high Xe contents and long discharge path condition. In this paper, a long gap ITO hump electrode (LGH) model for discharge cells of ac PDP is evaluated in the various Xe contents($5{\sim}20%$). The discharge voltage of LGH structure is lower about 30V than that of ITa reference structure with same main discharge gap. The LGH structure has lower power consumption and higher luminance than those of reference structure, respectively. Also, the luminous efficacy of LGH structure is higher about 20% than that of ITO reference structure in the 20% Xe contents.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.5
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• pp.827-832
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• 2008

One of the most important issues in AC PDP is luminance and luminous efficacy. To improve the luminance and luminous efficacy, new sustain electrode structure which contains long discharge gap is necessary. However, it causes a rise of firing voltage. In this experiment, a new structure is proposed in order to solve this problem. To drop the firing voltage, the hump shaped electrode is inserted into the forward area of the main discharge gap. The experimental results show that proposed structures with 160um discharge gap have high firing voltage by 38V, high luminance by 30% and high luminous efficacy by 15% compared with conventional type having 60um discharge gap. In addition, the proposed structure with hump electrode shows lower firing voltage by 24V compared with the test panel with 160um discharge gap which doesn't have hump electrode though they have similar luminous efficacy.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.167-169
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• 2016

The structure guide lines of pocket tunnel field effect transistor(TFET) considering Line and Point tunneling are introduced. As the pocket doping concentration or thickness increase, on-current $I_{on}$ increases. As the pocket thickness or gate insulator increase, subthreshold swing(SS) increases. Optimal structure reducing the hump effects should be proposed in order to enhance SS.

• Proceedings of the KOR-KST Conference
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• 1999.10a
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• pp.129-134
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• 1999

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.711-714
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• 2003

In this presentation, we investigated the abnormal subthreshold slope of the FD SOI MOSFETs upon the rapid thermal annealing. Based on subthreshold technique and C-V measurement, we deduced that the hump of the subthreshold slope comes from the abnormal D$_{it}$ distribution after RTA. The local kink in the interface trap density distribution by RTA drastically degrades the subthreshold characteristics and mini hump can be eliminated by S-PGA.A.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.2
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• pp.232-242
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• 2015

Analytical study of surface recombination at the $Si/SiO_2$ interface is carried out in order to set the optimum surface conditions that result in minimum dark base current and maximum open circuit voltage in silicon solar cells. Recombination centers are assumed to form a continuum rather than to be at a single energy level in the energy gap. It is shown that the presence of a hump in the dark I-V characteristics of high efficiency PERL cells is due to the dark current transition from a high surface recombination regime at low voltage to a low surface recombination regime at high voltage. Successful fitting of reported dark I-V characteristics of a typical PERL cell is obtained with several possible combinations of surface parameters including equal electron and hole capture cross sections.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.261-267
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• 2008

One of the most important issues in fence-type PDP is low luminance and luminous efficiency. To improve luminance and luminous efficiency, new sustain electrode structure which contains long discharge gap is necessary. However, it causes rise of firing voltage. In this paper, a new fence electrode structure is proposed in order to solve these problems. To drop the firing voltage, tow hump shaped electrodes is added on the main discharge electrode, and distance between two humps is controlled. The experimental results show that the test panel with the narrow horizontal gap(40um) between two humps shows low firing voltage by 17V compared with 80um gap in spit of similar luminance and luminous efficiency.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.1
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• pp.67-73
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• 2002

The flexibility of long reach manipulators presents a difficult control problem when accurate end-point position is required. Input shaping by convolving system commands with impulse sequences has been shown to be an effective method of reducing residual vibrations in flexible systems. However, existing shapers have been considered robustness fur only frequency uncertainty. However, this paper presents new multi-hump convolution(CV) input shaper that could accommodate with the simultaneous variation of natural frequency and damping ratio. Comparisons with previously proposed input shapers are presented to illustrate the qualities of the new input shaper. These new shapers will be shown to have better robustness fur the variation of frequency and damping ratio.