• Journal of Broadcast Engineering
• /
• v.14 no.2
• /
• pp.197-209
• /
• 2009

Stereoscopic video delivers depth perception to users contrary to 2D video. Therefore, we need to develop a new video quality assessment model for stereoscopic video. In this paper, we propose a new method for objective assessment of stereoscopic video. The proposed method detects blocking artifacts and degradation in edge regions such as in conventional video quality assessment model. And it detects video quality difference between views using depth information for efficient quality prediction. We performed subjective assessment of stereoscopic video to check the performance of the proposed method, and we confirmed that the proposed algorithm is superior to the existing method in PSNR in respect to correlation with results of the subjective assessment.

• ETRI Journal
• /
• v.38 no.2
• /
• pp.272-279
• /
• 2016

In this paper, a new structure for an advanced high holding voltage silicon controlled rectifier (AHHVSCR) is proposed. The proposed new structure specifically for an AHHVSCR-based electrostatic discharge (ESD) protection circuit can protect integrated circuits from ESD stress. The new structure involves the insertion of a PMOS into an AHHVSCR so as to prevent a state of latch-up from occurring due to a low holding voltage. We use a TACD simulation to conduct a comparative analysis of three types of circuit - (i) an AHHVSCR-based ESD protection circuit having the proposed new structure (that is, a PMOS inserted into the AHHVSCR), (ii) a standard AHHVSCR-based ESD protection circuit, and (iii) a standard HHVSCR-based ESD protection circuit. A circuit having the proposed new structure is fabricated using $0.18{\mu}m$ Bipolar-CMOS-DMOS technology. The fabricated circuit is also evaluated using Transmission-Line Pulse measurements to confirm its electrical characteristics, and human-body model and machine model tests are used to confirm its robustness. The fabricated circuit has a holding voltage of 18.78 V and a second breakdown current of more than 8 A.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.1018-1019
• /
• 2015

Recently, standby power reduction techniques of AC/DC adaptor were developed, consuming power almost arrived to 300mW level. The standby power losses are composed of the input filter loss 11.8mW, the control IC for AC/DC adaptor 18mW, the switching loss 9.53mW and the feedback loss 123mW. And there are the standby power reduction techniques. In this paper, in order to reduce the standby power of SMPS more, the loss due to a voltage difference between input and output is reduced by the control circuit which is composed of the low voltage driving circuit and voltage regulator. The low voltage driving circuit operates on the low voltage of input and off the high voltage. The low voltage driving IC was produced by the $1.0{\mu}m$, high voltage DMOS process.

• ETRI Journal
• /
• v.37 no.6
• /
• pp.1188-1198
• /
• 2015

In this paper, a multi-time programmable (MTP) cell based on a $0.18{\mu}m$ bipolar-CMOS-DMOS backbone process that can be written into by using dual pumping voltages - VPP (boosted voltage) and VNN (negative voltage) - is used to design MTP memories without high voltage devices. The used MTP cell consists of a control gate (CG) capacitor, a TG_SENSE transistor, and a select transistor. To reduce the MTP cell size, the tunnel gate (TG) oxide and sense transistor are merged into a single TG_SENSE transistor; only two p-wells are used - one for the TG_SENSE and sense transistors and the other for the CG capacitor; moreover, only one deep n-well is used for the 256-bit MTP cell array. In addition, a three-stage voltage level translator, a VNN charge pump, and a VNN precharge circuit are newly proposed to secure the reliability of 5 V devices. Also, a dual memory structure, which is separated into a designer memory area of $1row{\times}64columns$ and a user memory area of $3rows{\times}64columns$, is newly proposed in this paper.

• ETRI Journal
• /
• v.39 no.5
• /
• pp.746-755
• /
• 2017

In this paper, an electrostatic discharge (ESD) protection circuit is designed for use as a 12 V power clamp by using a parasitic-diode-triggered silicon controlled rectifier. The breakdown voltage and trigger voltage ($V_t$) of the proposed ESD protection circuit are improved by varying the length between the n-well and the p-well, and by adding $n^+/p^+$ floating regions. Moreover, the holding voltage ($V_h$) is improved by using segmented technology. The proposed circuit was fabricated using a $0.18-{\mu}m$ bipolar-CMOS-DMOS process with a width of $100{\mu}m$. The electrical characteristics and robustness of the proposed ESD circuit were analyzed using transmission line pulse measurements and an ESD pulse generator. The electrical characteristics of the proposed circuit were also analyzed at high temperature (300 K to 500 K) to verify thermal performance. After optimization, the $V_t$ of the proposed circuit increased from 14 V to 27.8 V, and $V_h$ increased from 5.3 V to 13.6 V. The proposed circuit exhibited good robustness characteristics, enduring human-body-model surges at 7.4 kV and machine-model surges at 450 V.

• Journal of Power Electronics
• /
• v.12 no.6
• /
• pp.886-894
• /
• 2012

This paper presents a secondary-side, dual-mode feedback LLC resonant controller IC with dynamic PWM dimming for LED backlight units. In order to reduce the cost, master and slave outputs can be generated simultaneously with a single LLC resonant core based on dual-mode feedback topologies. Pulse Frequency Modulation (PFM) and Pulse Width Modulation (PWM) schemes are used for the master stage and slave stage, respectively. In order to guarantee the correct dual feedback operation, Phased-Locked Loop (PLL)-based automatic duty control circuit is proposed in this paper. The chip is fabricated using $0.35{\mu}m$ Bipolar-CMOS-DMOS (BCD) technology, and the die size is $2.5mm{\times}2.5mm$. The frequency of the gate driver (GDA/GDB) in the clock generator ranges from 50 to 425 kHz. The current consumption of the LLC resonant controller IC is 40 mA for a 100 kHz operation frequency using a 15 V supply. The duty ratio of the slave stage can be controlled from 40% to 60% independent of the frequency of the master stage.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.22 no.10
• /
• pp.801-807
• /
• 2009

In this paper, we propose a novel shoot-through protection circuit and pulse generator for half-bridge driver IC. We designed a robust half-bridge driver IC over a variation of processes and power supplies. The proposed circuit is composed a delay circuit using a beta-multiplier reference. The proposed circuit has a lower variation rate of dead time and pulse-width over variation of processes and supply voltages than the conventional circuit. Especially, the proposed circuit has more excellent pulse-width matching of set and reset signals than the conventional circuit. Also, the proposed pulse generator is prevented from fault operations using a logic gate. Dead time and pulse-width of the proposed circuit are typical 250 ns, respectively. The variation ratio is 68%(170 ns) of maximum over variation of processes and supply voltages. The proposed circuit is designed using $1\;{\mu}m$ 650 V BCD (Bipolar, CMOS, DMOS) process parameter, and the simulations are carried out using Spectre simulator of Cadence corporation.

• Journal of Information Display
• /
• v.13 no.2
• /
• pp.73-82
• /
• 2012

In this paper, a light-emitting diode (LED) backlight driver integrated circuit (IC) for medium-sized liquid crystal displays (LCDs) is proposed. In the proposed IC, a linear current regulator with matched internal resistors and an adaptive phase-shifted pulse-width modulation (PWM) dimming controller are also proposed to improve LED current uniformity and reliability. The double feedback loop control boost converter is used to achieve high power efficiency, fast transient characteristic, and high dimming frequency and resolution. The proposed IC was fabricated using the 0.35 ${\mu}m$ bipolar-CMOS-DMOS (BCD) process. The LED current uniformity and LED fault immunity of the proposed IC were verified through experiments. The measured power efficiency was 90%; the measured LED current uniformity, 97%; and the measured rising and falling times of the LED current, 86 and 7 ns, respectively. Due to the fast rising and falling characteristics, the proposed IC operates up to 39 kHz PWM dimming frequency, with an 8-bit dimming resolution. It was verified that the phase difference between the PWM dimming signals is changed adaptively when LED fault occurs. The experiment results showed that the proposed IC meets the requirements for the LED backlight driver IC for medium-sized LCDs.

• The Journal of the Acoustical Society of Korea
• /
• v.14 no.1E
• /
• pp.30-38
• /
• 1995

In this paper, we evaluated the performance of vocoders for three-way conferencing using signal summation technique in digital mobile communication network. The signal summation technique yields natural mode of three-way conferencing, in shich the mixed voice signal from two speakers are transmitted to a third person, though there has been no useful speech coding technique for the mixed voice signal yet. We established Qualcomm code term prediction (RPE-LTP) vocoders to provide three-way conferencing using signal summation techinique. In addition, as the conventional speech quality measures are not applicable to the vocoders for mixed voice signals, we proposed two kinds of subjective quality measures. These are the sentence discrimination (SD) test and the modified degraded mean opinion score (MDMOS) test. The experimental results show that the output speech quality of the VSELP vocoder is superior to other two.

• The Journal of the Korea Contents Association
• /
• v.5 no.5
• /
• pp.202-210
• /
• 2005

The public Information systems for destination marketing have poorly operated and failed to satisfy tourists' needs. Public tourism website mainly offers fundamental tourism information such as transportation, lodging and prime attractions, which is mainly specialized in commercial web sites, and fails to attract tourists. For the public benefits, marketing strategy publicl DMOs have to specialize their tourism information, and attract specific target markets. Thus, this study examined the effect of tourism motivations on information search behavior to figure out the importance of tourism information. The results show that the level of escapist motivation positively to the perceived importance of fundamental informations, and the level of activist motivation effects positively to the perceived importance of objective-specific informations. These results give show problems of regional tourism information site and implications are suggested.