병렬 인터페이스형 디지털/아날로그 변환회로의 1개 비트 확장에 관한 연구

권성열,이현창,Kwon, Sung-Yeol,Lee, Hyun-Chang 중소기업융합학회 2021 융합정보논문지 Vol.11 No.8

본 논문에서는 병렬 인터페이스형 디지털/아날로그 변환회로에 외부 소자를 추가해 1개 비트를 확장하는 방법을 제시했다. 이를 위해 디지털/아날로그 변환회로의 원리를 살펴보고 개별 소자를 추가해 1개 비트를 확장하는 경우에 발생되는 문제점을 분석했으며, 연산증폭기 회로를 이용한 디지털/아날로그 소자의 비트 확장 방법을 제시했다. 제시한 방법은 연산증폭기의 고정밀도 특성을 이용함에 따라 소자에 오차가 발생하더라도 출력파형의 전체적인 크기에만 영향을 미치고 각 비트 사이에서 발생하는 전압역전 현상은 발생하지 않는 특징을 지닌다. 제시한 방법의 효과를 확인하기 위해 실험회로를 구성해 출력의 절대전압 측정과 상대적 오차 측정을 실시한 결과 0.0756%의 전압오차가 나타남으로서 개별소자 추가에 의해 1개 비트 확장 시 요건인 0.195%를 충분히 충족함을 확인했다. In this paper, a method of extending 1 bit by adding an external device to a parallel interface type Digital-to-Analog conversion(D/A C) circuit is presented. To do this, the principle of the D/A C circuit was examined, and the problems that occur when extending one bit by adding individual devices were analyzed, and a bit extension method of the D/A devices using an OP-Amp. circuit was presented. As the proposed method uses the high-precision characteristics of the OP-Amp., even if an error occurs in the device, only the overall size of the output waveform is affected, and the voltage reversal phenomenon that occurs between each bit does not occur. In order to confirm the effect of the proposed method, an experimental circuit was constructed and the absolute voltage of the output and the relative error were measured. As a result, a voltage error of 0.0756% appeared, confirming that the 0.195% requirement for one bit expansion by adding individual devices was sufficiently satisfied.

Pyroelectric Characteristics of 0-3 PbTiO₃/P(VDF/TrFE) Nanocomposites Thin Films for Infrared Sensing

권성열,Kwon, Sung-Yeol Materials Research Society of Korea 2007 한국재료학회지 Vol.17 No.4

[ 0-3PbTiO_3/P$ ](VDF/TrFE) nanocomposites thin films for passive pyroelectric infrared sensor have been fabricated by two-step spin coating technique. 65 wt% VDF and 35 wt% TrFE was formed to a P(VDF/TrFE) poder Nano size $PbTiO_3$ powder was used. 0-3 connectivity of $PbTiO_3$(VDF/TrFE) composites film is achieved and also observed by SEM photography successfully. The dielectric constant, and pyroelectric coefficient measured and compared with P (VDF/TrFE). A very low dielectric constant (13.48 at 1 kHz) and high enough pyroelectric coefficient (3.101 $nC/cm^2$.k at $50^{circ}C$) neasured. This nanocomposites can be used for a new pyroelectric infrared sensor for better performance.

Pt 상대전극 성막 두께와 두 기판 간격에 따른 DSSC의 효율 특성

권성열,양욱,주택원,Kwon, Sung-Yeol,Yang, Wook,Zhou, Zeyuan 한국전기전자재료학회 2013 전기전자재료학회논문지 Vol.26 No.3

DSSCs electrical characteristics and efficiency fabricated with different tape casting thickness Pt counter electrodes and different thickness between $TiO_2$ photo electrode and Pt counter electrode substrate were studied. 1 layer Pt counter electrode shows 3.979% efficiency. Efficiency increased as tape casting thickness decreased. The lowest open-circuit voltage was a 0.726 V and the highest short-circuit current was a 2.188 mA on 1 layer Pt counter electrode. On the different thickness between two substrates, the lowest open-circuit voltage 0.712 V and the highest short-circuit current 2.787 mA was measured at $60{\mu}m$ surlyn film thickness and it shows the highest value of 5.067% efficiency.

TiO₂ Paste에 PEG 첨가에 따른 DSSC의 효율 특성

권성열,양욱,장자항,Kwon, Sung-Yeol,Yang, Wook,Zhang, Zi-Heng 한국전기전자재료학회 2014 전기전자재료학회논문지 Vol.27 No.11

Photo electrode is an important component of DSSC, so this paper did some research on it. Through the method of adding PEG additive into $TiO_2$ paste, the electrical characteristics and efficiencies of DSSCs with photo electrode surface area were studied. In the case of not adding PEG in $TiO_2$ paste, $26{\mu}m$ thickness $TiO_2$ photo electrode shows 5.081% efficiency. The highest short circuit current density was $10.476mA/cm2^$. The structure of porous $TiO_2$ film can be controlled through changing the PEG additive amount in $TiO_2$ paste and the molecular weight of PEG. When the additive amount of PEG 20,000 in $TiO_2$ paste reaches 5%, the peak efficiency with $26{\mu}m$ thickness $TiO_2$ photo electrode was 5.387% and its highest current density were $11.084mA/cm^2$.

광전극 두께와 표면적 변형에 따른 DSSC의 효율 특성

권성열,양욱,주택원,Kwon, Sung-Yeol,Yang, Wook,Zhou, Ze-Yuan 한국전기전자재료학회 2014 전기전자재료학회논문지 Vol.27 No.2

Photo electrode is an important component for DSSC. DSSCs electrical characteristics and efficiencies fabricated with different $TiO_2$ photo electrodes thickness and modified phoro electrode surface area were studied. $11{\mu}m$ $TiO_2$ photo electrode shows a 4.956% efficiency. The highest short circuit current density was a $9.949mA/cm^2$. Efficiencies and short circuit current density increased as tape casting thickness decreased. Modified surface area of the photo electrode by needle stamp processing were studied. 200 times needle stamp processing on photo electrodes shows a highest 5.168% efficiency. Also the short circuit current density was a $10.261mA/cm^2$.

Fabrication and Characteristics of Pyroelectric IR Sensor Using $1.6{\mu}m$ P(VDF/TrFE) thin film

권성열,Kwon, Sung-Yeol The Korean Sensors Society 2001 센서학회지 Vol.10 No.2

A pyroelectric senior using P(VDF/TrFE) film for sensing materials has been fabricated and evaluated with other commercial pyroelectric sensors that use ceramic materials for sensing. The device was mounted in a TO-5 housing to detect infrared light of $5.5{\sim}14\;{\mu}m$ wavelength. The NEP (noise equivalent power) and specific detectivity $D^*$ of the device were $2.13{\times}10^{-8}\;W$ and $9.37{\times}10^6\;cm/w$ respectively under emission energy of $13\;{\mu}W/cm^2$ respectively. These result shows a better characteristics than other commercial pyroelectric sensors NEP $8.08{\times}10^{-7}\;W$ and $D^*$ $2.47{\times}10^5\;cm/w$.

TTIP가 첨가된 저온소성용 TiO₂ Paste를 이용한 DSSC의 효율 특성

권성열,심창수,양욱,Kwon, Sung Yeol,Sim, Chang Soo,Yang, Wook 한국전기전자재료학회 2019 전기전자재료학회논문지 Vol.32 No.1

Recently, the application field of solar panels is increasing. Accordingly, the demand for flexible devices is also steadily increasing. It is therefore necessary to develop $TiO_2$ paste for low-temperature annealing for flexible DSSC fabrication. In this study, the $TiO_2$ paste for low-temperature annealing with varying molar ratio of titanium isopropoxide (TTIP) was prepared, and DSSC was fabricated and its characteristics were compared. As a result, there was no deformation of the particles on the surface in the SEM data. However, the highest open circuit voltage, short circuit current, and fill factor were measured in the DSSC unit cell prepared by adding 0.5 mol of TTIP to the $TiO_2$ paste, and the highest efficiency was 4.148%.

적외선 감지를 위한 0~3 PbTiO₃/P(VDF/TrFE) 복합체 필름의 향상된 초전 특성

권성열(Sung Yeol Kwon) 한국고분자학회 2011 폴리머 Vol.35 No.5

두 단계 스핀 코팅 방법을 사용하여 세라믹 체적 분율 0.10과 0.13의 PbTiO3/P(VDF/TrFE) 0~3형 복합재료를 제작하고 분석하였다. 0~3형 PbTiO3/P(VDF/TrFE) 복합재료를 SEM 전자현미경 사진으로 성공적으로 확인할 수 있었다. 이러한 전자현미경 사진을 통하여 복합재료의 0~3형 구조를 재확인하였다. 0~3형 PbTiO3/P(VDF/TrFE) 복합재료는 P(VDF/TrFE) 공중합체보다 센서용 전기적 특성이 우수함을 나타내었다. 그러므로 이러한 낮은 유전상수와 높은 초전계수를 나타내는 0~3형 PbTiO3/P(VDF/TrFE) 복합재료는 더 높은 성능을 나타낼 수 있는 새로운 초전형 센서 재료로 사용될 수 있다. PbTiO3/P(VDF/TrFE) 0~3 composites thin films with 0.10 and 0.13 of ceramic volume fraction factor have been fabricated by two-step spin coating technique and analyzed. 0~3 connectivity of PbTiO3/P(VDF/TrFE) composites film was observed successfully by SEM micrography. The SEM picture confirmed 0~3 connectivity. And, in all the properties, 0~3 PbTiO3/P(VDF/TrFE) composites film was superior to P(VDF/TrFE) copolymer. Therefore, with a good low-dielectric constant and a high pyroelectric coefficient, the composite thin films can be used for a new pyroelectric infrared sensor of higher performance.

TiO₂광전극 두께와 소성온도 상승 방식에 따른 DSSC의 효율 특성

권성열(Sung-Yeol Kwon),양욱(Wook Yang) 대한전기학회 2012 대한전기학회 학술대회 논문집 Vol.2012 No.5

P(VDF/TrFE) 필름의 두께에 따른 인체 감지형 초전형 PIR 적외선 센서의 특성

권성열 ( Sung Yeol Kwon ) 한국센서학회 2011 센서학회지 Vol.20 No.2

A thick 25 μm thickness poled P(VDF/TrFE) film pyroelectric infrared ray sensor has been fabricated and then thin 1.6 μm thickness P(VDF/TrFE) film pyroelectric infrared ray sensor has been fabricated also. These thick and thin P(VDF/TrFE) film pyroelectric infrared ray sensor was mounted in TO-5 housing to detect infrared light of 5.5~14 μm wavelength for human body detecting with each other. The noise output voltage of the thick P(VDF/TrFE) film pyroelectric infrared ray sensor were 380 mV and NEP(noise equivalent power) is 3.95×10-7 W which is the similar value with the commercial pyroelectric nfrared ray sensor using ceramic materials as a sensing material. The NEP and specific detectivity D* of the thin P(VDF/TrFE) film pyroelectric infrared ray sensor were 2.13×10-8 W and 9.37×106 cm/W under emission energy of 13 μW/cm2 respectively. These result caused by lower thermal diffusion coefficient of a thin 1.6 μm thickness PVDF/TrFE film than the thick 25 μm thickness poled P(VDF/TrFE) film pyroelectric infrared ray sensor.