Browsing by Author "Huang, YC"

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A CMOS delta-sigma true RMS converter
(2000-02-01)
Wey, WS
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Huang, YC
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
Conventionally, monolithic electronics true rms converters are constructed by bipolar circuitry, This paper describes a new architecture based on delta-sigma (Delta Sigma) modulation to realize a low-cost rms converter in CMOS technologies, especially intended for handheld digital multimeters. The signal-to-quantization noise ratio as well as transfer characteristics of this architecture have been deduced to obtain initial design parameters. The use of an indirect charge transfer technique makes the converter gain depend only on an on-chip capacitor ratio, reducing gain drift and offering good gain accuracy, Measured results show that this converter achieves a signal-to-noise ratio of 88 dB and a relative error of +/-0.2% for arbitrary inputs with a signal crest factor up to three. The signal bandwidth exceeds 50 kHz, and the full-scale input range is greater than 0.4 V-rms. Without trimming and calibration, this converter has an absolute gain error less than +/-0.4%. This chip is fabricated in a 0.8-mu m double-poly; double-metal CMOS process and occupies active area of 1 mm(2).
A CMOS rms-to-dc converter using Delta Sigma multiplier-divider
(1999)
Wey, WS
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Huang, YC
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
A novel topology for CMOS Delta Sigma rms-to-dc converters is described. Analysis shows that the proposed topology is insensitive to most circuit imperfections except offset voltages. A test circuit of a 1st-order single-ended rms-to-dc converter is realized in a 0.8 mu m double-poly CMOS process. Experimental results demonstrate that input waveforms with crest factors as high as 3 can be measured at the 800mV full-scale input level. It provides a maximum relative error of +/-1% of reading.
A methodology for fault model development for hierarchical linear systems
(2000)
Huang, YC
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Lee, CL
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Lin, JW
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Chen, JE
;
Su, CC
In this paper, a methodology to develop fault models for hierarchical linear systems which are composed of operational amplifiers(OP) is demonstrated and presented. The methodology, at first, presents a transfer function model for the open-loop OP based on analysis of element faults at the transistor level. Then it derives a transfer function model for the closed loop OP based on the derived open-loop OP level model, again a higher level fault model for a module which is composed of closed loop OPs. The models can handle ac faults. The benchmark state-variable filter is used as an example to demonstrate for this methodology. an application of the derived models to Monte-Carlo simulation to save computation time is also demonstrated.
A new pre-etching pattern to determine < 110 > crystallographic orientation on both (100) and (110) silicon wafers
(2005-02-01)
Chang, WH
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Huang, YC
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
Since the etching rate of anisotropic wet etching of silicon is highly orientation-dependent, it is important to determinate the crystallographic orientation before etching. In this paper, a new mask pattern based on the pre-etching process is designed to find out the <110> crystal orientation on both (100) and (110) silicon wafers observably and to align the subsequent masks more easily and conveniently. Because of a compensation of the quantization error due to the limitated scanning resolution of a mask generator and an optimum design, a pre-etching mask pattern with a resolution of 0.00625degrees and a span angle of +/-2degrees is achieved with a consumption area of 560 x 14,472 mum(2). To evaluate the precision of the misorientation angle determined by the pre-etching process based on the proposed pattern, both (100) and (110) wafers with 60 pre-etching patterns on each of them were etched. After statistic analysis, the precision of +/-0.0467degrees for (100) wafers and +/-0.025degrees for (110) wafers are achieved in our experiments which suggest the precision of determination of the crystallographic misorientation by the preetching process may be limited even though the resolution of the pre-etching mask pattern is high.
A novel structural design for force/torque fingertip sensors
(1998-08-01)
Chang, YH
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Huang, YC
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Liu, YP
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Tsay, SM
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電子工程學系及電子研究所
This work presents a novel structural design of force/torque fingertip sensors for sensing planar forces. The resolution can be increased by reducing the condition number of the calibration matrix and the sensitivity can be enhanced by placing strain gauges at specified positions. Moreover, the interaction from off-axis loads is intrinsically negligible in our design. A relatively simple and accurate calibration method for performance evaluation is introduced. Some experimental results are presented to demonstrate the capability of the proposed design.
Alignment error evaluation of the dial pattern
(1998-09-01)
Chang, YH
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Huang, YC
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電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
To achieve smooth etched sidewall surface at minimal time expense and reduce undercut etching are basic disciplines of the task of accurate alignment. When aligning etch-masks to [110] crystal orientation on a [100] Si wafer, a consideration is proposed by Schroder who uses a dial pattern for pre-etching to determine [110] crystal orientation. But that performance depends strongly on the resolution of the mask pattern generator. In this paper, we analyse Schroder's method by mathematical modeling and computer simulation. Finally, we propose an improvement for the Schroder limitation according to our analytic results.
Color image vehicular detection systems with and without fuzzy neural network: A comparison
(2003-09-01)
Lan, LW
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Kuo, AY
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Huang, YC
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運輸與物流管理系註：原交通所+運管所
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Department of Transportation and Logistics Management
This paper develops a color image vehicular detection (CIVD) system in which background differencing technique is employed to detect whether a vehicle passes through the detecting points equally spaced out on a pseudo line detector. Two methods (interval search and regression) are tried to determine the optimal crisp threshold values to cope with various lighting conditions. To compare the detection performance with and without incorporating a fuzzy neural network (FNN), a three-layer FNNCIVD system is further designed with trapezoidal membership function and network parameters trained by back propagation algorithm. Under different environments (freeway and urban street) with various lighting conditions (daytime and nighttime), it is found that the detection success rates for interval-search CIVD and regression CIVD are about the same. However, both perform worse than the FNNCIVD system in which about 90% success rates are reported with seven detection points. Compared with the interval-search CIVD system, the FNNCIVD system can increase the success rates at a range of 14% to 22% on the freeway mainline and 18% to 26% on the urban street. It is also found that daytime detection performance is slightly better than nighttime detection. Possible reasons for missed detection and false detection are discussed.
Comment on "Application of BEM with extended Kalman filter to parameter identification of an elastic plate under dynamic loading" by M. Tanaka, T. Matsumoto and H. Yamamura [Engineering Analysis with Boundary Elements 28 (2004) 213-219]
(2005-01-01)
Yeh, HD
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Huang, YC
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環境工程研究所
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Institute of Environmental Engineering
Compact efficient passively Q-switched Nd : GdVO4/PPLN/Cr4+: YAG tunable intracavity optical parametric oscillator
(2005-11-14)
Tsai, LY
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Chen, YF
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Lin, ST
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Lin, YY
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Huang, YC
We report on a compact efficient diode pumped passively Q-switched Nd:GdVO4/ Cr4+:YAG/ PPLN intracavity optical parametric oscillator (OPO) with a shared-resonator configuration. Experimental results reveal that the amplitude stability of the shared-resonator configuration is substantially superior to that of the conventional coupled-resonator configuration. At a diode pump power of 15 W, the compact intracavity OPO cavity produces the average power greater than 900 mW with a pulse repetition rate of 36 kHz. The output pulses noticeably display the mode-locking phenomenon that leads to the maximum peak power to be higher than 20 kW. (c) 2005 Optical Society of America.
Efficient generation of continuous-wave yellow light by single-pass sum-frequency mixing of a diode-pumped Nd : YVO4 dual-wavelength laser with periodically poled lithium niobate
(2002-10-15)
Chen, YF
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Tsai, SW
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Wang, SC
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Huang, YC
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Lin, TC
We report efficient generation of cw yellow light by use of single-pass sum-frequency mixing from a diode-pumped Nd:YVO4 dual-wavelength laser with periodically poled lithium niobate. A diode-pumped Nd:YVO4 dual-wavelength laser is implemented with a three-mirror cavity, and the optimum oscillation condition is obtained from theoretical analysis. We extracted 78 mW of power at 593 run from 1.2 W at 1064 nm and from 1.0 W at 1342 nm in a beam with excellent quality. The output power could probably be increased to similar to92 mW by antireflection. coating of the crystal. (C) 2002 Optical Society of America.
Electrochemical etching of n-type 6H-SiC without UV illumination
(2006-06-01)
Chang, WH
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Schellin, B
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Obermeier, E
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Huang, YC
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交大名義發表
Deep etching of n-type 6H-SiC using a two-step etching process has been studied. First, anodization of 6H-SiC in an HF electrolyte (2 wt.%) without ultraviolet light is applied to form a deep porous layer with the desired dimensions. Then, a thermal oxidation process is used to oxidize this porous layer. The oxidized layer is then removed in a concentrated HF solution. In the experiments, the etching parameters electrolyte concentration and current density are optimized in order to obtain a uniform pore size and hence, a smooth etched surface. After adjusting these parameters, the porous layer formation experiments are carried out at 20 degrees C in a 2 wt.% HF electrolyte using a current density of 50 mA/cm(2). The corresponding porous layer formation rate is about 1.1 mu m/min. To demonstrate the capabilities of this SiC bulk micromachining process, deep circular cavities are fabricated in n-type 6H-SiC substrates.
Electromagnetic resonance in deformed split ring resonators of left-handed meta-materials
(2004-08-15)
Hsu, YJ
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Huang, YC
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Lih, JS
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Chern, JL
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光電工程學系
Recently, structures called deformed split ring resonators have been proposed to achieve the smallest volume of a unit cell, while retaining negative permeability. With a combination of wire structures, the characteristics of a negative index of refraction, or left-handed meta-materials, can be seen from the transmission spectrum. This electromagnetic resonance, including its orientation tolerance and angular dependence on the incident beam, is explored in detail in the microwave range. (C) 2004 American Institute of Physics.
Evidence of birefringence and anomalous electromagnetic-pulse propagation in an organic light-emitting diode
(2005-06-05)
Tai, SC
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Chern, JL
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Huang, YC
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Tseng, MR
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Lin, HK
dHigh-speed electromagnetic characteristics of an organic light-emitting diode (OLED) are explored in this paper. When a high-frequency (similar to 14 GHz) microwave pulse is injected into an OLED, the pulse is split into two peaks: one peak is delayed by 1.725 ns and another one is advanced by 0.183 ns, which also suggests the existence of an extremely low-speed group velocity. The effective thickness of the OLED sample is similar to 355.8 nm and, as a result, the effective index of refraction is similar to 107 when the splitting phenomenon occurs. (c) 2005 Wiley Periodicals, Inc.
Experimental realization of breaking diffraction limit by planar negative-index metamaterials in free space
(2005-02-01)
Lih, JS
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Wang, YS
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Lu, MC
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Huang, YC
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Chen, KH
The sharpness of the image formed by a conventional lens is always limited by the wavelength of light. Recently, Pendry proposed a superlens, with a negative refractive index. such that the resolution is not limited by wavelength. Herein, we report direct experimental evidence of Pendry's superlens breaking the diffraction limit, in the microwave range of the X band (8-12 GHz), with a periodic array of split ring resonators and continuous wires; i.e. a meta-material with negative index of refraction.
Fuzzy neural incident detection algorithms with rolling training procedure
(2003)
Lan, LW
;
Huang, YC
;
運輸與物流管理系註：原交通所+運管所
;
Department of Transportation and Logistics Management
This paper attempts to establish a fuzzy neural automatic incident detection (FNAID) algorithm, using back-propagation training procedures. A rolling training procedure continuously updating the traffic flow parameters is proposed to enhance the adaptability of FNAID to different traffic flow conditions. A real incident case is deliberately generated to calibrate the traffic simulator-Paramics. To validate the FNAID with and without rolling training procedure, the calibrated Paramics is used to simulate sufficient incident samples. The off-line tests and statistic tests conclude that under various traffic flow conditions, the FNAID with rolling training procedure has better detection performance than the one without rolling.
High-resolution MOS magnetic sensor with thin oxide in standard submicron CMOS process
(1996-10-01)
Yang, HM
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Huang, YC
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Lei, TF
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Lee, CL
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Chao, SC
In this paper, new results obtained with an NMOS magnetic-field sensor made by an industrial 0.8 mu m CMOS process are presented. The major disadvantage of MOS magnetic sensors, a larger noise, can be overcome by the submicron CMOS process with 19 nm gate oxide, The device with W/L=60 mu m/50 mu m biased at saturation region has a resolution of 150 nT (Hz)(-1/2) at 1 kHz and 400 nT (Hz)(-1/2) at 100 Hz, respectively. Even when the device size is scaled down to W/L=6 mu m/5 mu m, the resolution still has the value of 1.5 mu T (Hz)(-1/2) at 1 kHz. The dependence of sensitivity and current-related sensitivity for various bias conditions is discussed in detail and a simple model to explain these trends is established.
Intracavity PPLN crystals for ultra-low-voltage laser Q-switching and high-efficiency wavelength conversion
(2005-06-01)
Chen, YH
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Huang, YC
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Lin, YY
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Chen, YE
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電子物理學系
We report to the best of our knowledge the lowest switching voltage in an electro-optically Q-switched Nd: YVO4 laser by using a 13-mm long, 14-μ m-period PPLN crystal as a Pockels cell. A switching voltage as low as &SIM; 50V in the PPLN crystal was sufficient to hold off the lasing of the Q-switched laser at a pump power more than two times above its continuous-wave threshold. When the PPLN Q-switch was driven by a 100-V voltage at 6.5 kHz, we obtained 0.9-kW laser peak power from this 1-W diode-pumped Nd: YVO4 laser system with 13% output coupling. When the PPLN Pockels cell was cascaded with a 5-cm long, 30-μ m-period PPLN crystal, we produced &SIM; μ J/pulse energy at 1.59 μ m from optical parametric generation inside the actively Q-switched laser.
MOS magnetic current sensor based on standard CMOS process
(1997-03-27)
Yang, HM
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Lei, TF
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Huang, YC
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Lee, CL
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電子工程學系及電子研究所
A novel current sensor is proposed. The current sensor consists of one MOS magnetic sensor and a flat coil in an industrial CMOS process, An experimental device demonstrated a sensitivity of 8.4mV/A.
MOS magnetic current sensor based on standard CMOS process
(1997-03-27)
Yang, HM
;
Lei, TF
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Huang, YC
;
Lee, CL
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電子工程學系及電子研究所
A novel current sensor is proposed. The current sensor consists of one MOS magnetic sensor and a flat coil in an industrial CMOS process, An experimental device demonstrated a sensitivity of 8.4mV/A.
Parameter estimation for leaky aquifers using the extended Kalman filter, and considering model and data measurement uncertainties
(2005-02-01)
Yeh, HD
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Huang, YC
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環境工程研究所
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Institute of Environmental Engineering
A method using the extended Kalman filter (EKF) is proposed to identify the hydraulic parameters in leaky aquifer systems both with and without considering the aquitard storage. In the case without considering the aquitard storage, Hantush and Jacob's model combined with EKF can optimally determine the parameters for the leaky aquifer when analyzing the drawdown data. Coupled with Neuman and Witherspoon's model, the EKF is also employed to estimate the four parameters of aquifers. The observed drawdown data may be either interpolated using the Lagrangian polynomial or recursively used while implementing the EKF. The proposed method can identify the parameters, using part of the interpolated drawdown data or recursively used data, and obtains results with good accuracy. In the field-pumping test, a long pumping time may not be necessary if the proposed method is implemented on a computer, which is connected to pressure transducers and a data logger. In the process of parameter estimation, the leakage coefficient changes marginally for the first few observations. This phenomenon reflects the fact that there is a time lag between the start of pumping and the leakage effect on the drawdown. The analyses of the data uncertainty demonstrate that the EKF approach is applicable for drawdown data even when it contains white noise or temporal correlated noise. Finally, the choice between Hantush and Jacob's model and Neuman and Witherspoon's model depends on the hydrogeological condition of the aquifer system indicated in the analyses of the model uncertainty. Hantush and Jacob's model is shown to be a good choice for representing the leaky aquifer system if, the aquitard storage is comparatively small. (C) 2004 Elsevier B.V. All rights reserved.