Browsing by Author "Chen, Hung-Wei"

Now showing 1 - 13 of 13

A 4.2 nW and 18 ppm/degrees C Temperature Coefficient Leakage-Based Square Root Compensation (LSRC) CMOS Voltage Reference
(2019-05-01)
Huang, Chao-Jen
;
Lai, Yan-Jiun
;
Yang, Yu-Jheng Ou
;
Chen, Hung-Wei
;
Kuo, Chun-Chieh
State-of-the-art CMOS-based voltage reference suffer from a trade-off between power dissipation and temperature coefficient (TC) due to the limited order of compensation in an advanced process which features a low supplied voltage (1 similar to 1.2 V). The proposed voltage reference with leakage-based square root compensation (LSRC) technique bias the substrate to offset TC with ultra-low leakage current (100 similar to 300 pA). On the other hand, the architecture provides an extensible order of compensation which is independent of voltage headroom. The two LSRC branches voltage reference implemented in 40 nm CMOS process achieves a within-wafer sigma/mu of 0.204 and a TC of 18 ppm/degrees C with a power consumption of 4.2 nW.
A Fully Integrated Asymmetrical Shunt Switched-Capacitor DC-DC Converter With Fast Optimum Ratio Searching Scheme for Load Transient Enhancement
(2019-09-01)
Lin, Yen-Ting
;
Lai, Yan-Jiun
;
Chen, Hung-Wei
;
Yang, Wen-Hau
;
Ma, Yu-Sheng
This paper presents a modified negator-based switched-capacitor (NSC) dc-dc converter to achieve fine-grained voltage conversion ratios. Based on a concept of reconfiguring several 2: 1 switched-capacitor (SC) converters in series and parallel at the last stage, the proposed asymmetrical shunt SC (ASSC) converter provides more controllable variables of forward gain and feedback gain to decide different power path interconnections and increase the available conversion ratios, with a little sacrifice of its slow switching limit output impedance. The switching loss of the bottom-plate parasitic capacitance in the ASSC converter is less than the switching loss of the NSC topology because the two moderate voltages instead of the power rail are fed to the last stage 2: 1 SC unit and reduce the voltage swing. The bottom-plate swapping prototype further reduces the parasitic loss at high conversion ratios. To handle a large number of conversion ratios in closed-loop regulation, the ASSC converter uses the fast optimum ratio searching (FORS) technique, which evaluates the transient voltage drop to quickly search for target ratios and reduce the transient recovery time. A three-stage ASSC converter achieving 187 conversion ratios is fully integrated in the test chip, which is fabricated in 0.25-mu m CMOS process with an active area of 7.14 mm(2). Furthermore, 2389 conversion ratios can be derived in theory for a four-stage ASSC converter. The proposed reconfigurable SC converter provides an output voltage range of 0.4 to 2.8 V under no load conditions, and greater than 80% power efficiency at an output voltage level of 0.9 to 1.5 V over a load range of 3 to 9.5 mA. Due to the FORS technique, the measured transient recovery time is reduced from 7 to 1.5 mu s in case of load current step of 7 mA.
A Single-Inductor Dual-Output Converter with Linear-Amplifier-Driven Cross Regulation for Prioritized Energy-Distribution Control of Envelope-Tracking Supply Modulator
(2017-01-01)
Yang, Shang-Hsien
;
Lin, Yen-Ting
;
Ma, Yu-Sheng
;
Chen, Hung-Wei
;
Chen, Ke-Horng
A True-Random-Number-Based Pseudohysteresis Controller for Buck DC-DC Converter in High-Security Internet-of-Everything Devices
(2020-03-01)
Yang, Wen-Hau
;
Chiu, Shao-Wei
;
Kuo, Chun-Chieh
;
Lin, Yen-Ting
;
Lai, Yan-Jiun
For high-security Internet-of-Everything (IoE) devices, a true random number (TRN)-based pseudohysteresis controller (PHC) is proposed to avoid both power side-channel attack (PSCA) and power injection attack (PIA) and reduce electromagnetic interference (EMI) without degrading performance of transient response and regulation. In addition, the TRN-based PHC uses an enhanced security randomizer to correctly generate a random number (RN) independent of the input power at the PSCA and PIA and converts the RN into a hysteresis window that constitutes the true random modulation switching frequency. Therefore, the TRN-based PHC ensures proper spread spectrum and low EMI. In addition, fast transient response is maintained due to inherent hysteresis control. Experimental results show that peak EMI noise is reduced from 89.72 to 54.32dBV and meets the specification of EN 55032 Class B even under the PIA interference up to 1 V. Furthermore, in case of 0.2A-to-0.8A load step, the method achieves a recovery time of 7.3 s and an output voltage drop of 53 mV at a switching frequency of approximately 1 MHz, and the peak efficiency is 92.4.
A W-band Quadrature Hybrid Coupled Substrate Integrated Waveguide Diplexer
(2015-01-01)
Cheng, Yu-Liang
;
Chen, Hung-Wei
;
Huang, Peng-Da
;
Chang, Chi-Yang
;
電機工程學系
A W-band quadrature hybrid coupled substrate integrated waveguide (SIW) diplexer is proposed in this paper. Instead of conventional 0.127 mm substrate for W-band circuitry, a 0.254 mm substrate is chosen for Q-value improvement. A WR-10 waveguide to 0.254 mm SIW transition is developed for measurement purpose. The diplexer comprises four Riblet short slot quadrature hybrids and two pairs of 3-pole SIW channel filters. The two passbands of the diplexer are 84 GHz 6% BW and 93 GHz 6% BW respectively. The measured results matched well with simulated ones.
Characterizing the channel backscattering behavior in nanoscale strained complementary metal oxide semiconductor field-effect transistors
(2006-11-01)
Lin, Hono-Nien
;
Chen, Hung-Wei
;
Ko, Chih-Hsin
;
Ge, Chung-Hu
;
Lin, Horng-Chih
This work investigates the impact of different uniaxial strain polarities on channel backscattering in nanoscale complementary metal oxide semiconductor field-effect transistor (CMOSFET). Two carrier statistics, nondegenerate and degenerate-limited, are employed to extract the channel backscattering ratio, ballistic efficiency, and related backscattering factors. While the channel length scales down and the channel stress level increases further, the modulation of channel backscattering ratio, i.e., improved (degraded) by uniaxial tensile (compressive) strain, becomes more prominent. This observation holds true under both carrier statistics, which implies that the nondegenerate case with simple mathematics can be fairly used for evaluation. In addition, the correlation between strain-enhanced mobility gain and drain current improvement is found to be predicted well by the ballistic efficiency deduced with the nondegenerate carrier statistics.
Correlating drain-current with strain-induced mobility in nanoscale strained CMOSFETs
(2006-08-01)
Lin, Hong-Nien
;
Chen, Hung-Wei
;
Ko, Chih-Hsin
;
Ge, Chung-Hu
;
Lin, Horng-Chih
The correlation between channel mobility gain (Delta mu), linear drain-current gain (AIdlin), and saturation draincurrent gain (Delta I-dsat) of nanoscale strained CMOSFETs are reported. From the plots of Delta I-dlin versus Delta I-dsat and ballistic efficiency (B-sat,B-PSS), the ratio of source/drain parasitic resistance (R-sat,R-PSS) to channel resistance (R-CH,R-PSS) of strained CMOSFETs can be extracted. By plotting Delta mu versus Delta I-dlin, the efficiency of Delta mu translated to Delta I-dlin is higher for strained pMOSFETs than strained nMOSFETs due to smaller R-SD,R-PSS-to-R-CH,R-PSS ratio of strained pMOSFETs. It suggests that to exploit strain benefits fully, the R-SD,R-PSS reduction for strained nMOSFETs is vital, while for strained pMOSFETs the Delta I-dli -to-Delta mu sensitivity is maintained until R-SD,R-PSS becomes comparable to/or higher than R-CH,R-PSS.
Development of a Growth- Hormone- Conjugated Nanodiamond Complex for Cancer Therapy
(2014-05-01)
Chu, Hsueh-Liang
;
Chen, Hung-Wei
;
Tseng, Shin-Hua
;
Hsu, Ming-Hua
;
Ho, Li-Ping
It is highly desirable to develop a therapeutic, observable nanoparticle complex for specific targeting in cancer therapy. Growth hormone (GH) and its antagonists have been explored as cancer cell-targeting molecules for both imaging and therapeutic applications. In this study, a low toxicity, biocompatible, therapeutic, and observable GH-nanoparticle complex for specifically targeting growth hormone receptor (GHR) in cancer cells was synthesized by conjugating GH with green fluorescence protein and carboxylated nanodiamond. Moreover, we have shown that this complex can be triggered by laser irradiation to create a nanoblast and induce cell death in the A549 non-small-cell lung cancer cell line via the apoptotic pathway. This laser-mediated, cancer-targeting platform can be widely used in cancer therapy.
ESD Improvements on Power N-Channel LDMOS Devices by the Composite Structure of Super Junctions Integrated With SCRs in the Drain Side
(2020-01-01)
Chen, Hung-Wei
;
Chen, Shen-Li
;
Huang, Yu-Ting
;
Chen, Hsun-Hsiang
;
電子工程學系及電子研究所
This paper studies a composite power n-channel lateral-diffused MOSFET device with a super junction (SJ) and parasitic silicon-controlled rectifier structure (nLDMOS-SJ-SCR) in the drain side, which can be used for electrostatic discharge (ESD) and latch-up (LU) reliability enhancements of 60-V power electronics. For ESD and LU protection considerations, the drain side with an SJ structure integrated with p-n-p- and n-p-n-arranged types of nLDMOS-SCR transistors is demonstrated. According to the experimental data, the layout of the SJ structure in the drain side has positive effects on ESD and LU capabilities. The layout type of nLDMOS-SJ with a pillar width W = 9 mu m has the highest secondary breakdown current (I-t2) values; the ESD (LU) improvement was 46.3% (13.3%) compared with the nLDMOS reference sample. Meanwhile, an nLDMOS-SJ with a pillar width W = 27 mu m has the highest figure of merit (FOM) value. By contrast, an embedded p-n-p-(n-p-n-)arranged type SCR structure was added into the drain side once again. Initially, it has a positive (negative) effect on the ESD reliability. Furthermore, the ESD (figure of merit; FOM) improvement was 37.9% (13.72%) of the corresponding nLDMOS-SJ device for nLDMOS-SJ-SCR (p-n-p) with W = 27 mu m. Overall, an nLDMOS-SJ device integrated with the p-n-p-arranged-type SCR in the drain side is a favorable choice for ESD and LU improvements.
HfO2 Trap Layer Nonvolatile Flash Memory on SiGe Channel
(2014-01-01)
Lin, Yu-Hsein
;
Li, Jyun-Han
;
You, Hsin-Chiang
;
Hong, Jin-Shi
;
Tsai, Wan-Ting
This paper study a novel nonvolatile memory by using HfO2 trapping layer on epi-SiGe (Ge: 15%) channel. Because SiGe has a smaller bandgap than that of silicon, it can increases the electron/hole injection and enhances the program/erase speed. This study compares the characteristics of HfO2 memories with different tunnel oxynitride thicknesses on epi-SiGe substrate. The results show that the nonvolatile memory has superior characteristics in terms of considerably large memory window, high speed program/erase, long retention time, good endurance for future low power applications.
Strain-induced channel backscattering modulation in nanoscale CMOSFETs
(2006)
Chen, Hung-Wei
;
Lin, Hong-Nien
;
Ko, Chih-Hsin
;
Ge, Chung-Hu
;
Lin, Horng-Chih
The channel backscattering ratios as well as the ballistic efficiency of strained CMOSFETs were studied for both nondegenerate and degenerate-limited cases. We found that the simple nondegenerate assumption can predict strain-induced change of ballistic efficiency with fair accuracy. The mechanism of drain current dependence on strain-induced mobility change was also investigated based on channel backscattering theory.
Synthesis of Apolipoprotein B Lipoparticles to Deliver Hydrophobic/Amphiphilic Materials
(2013-08-14)
Chu, Hsueh-Liang
;
Cheng, Tsai-Mu
;
Chen, Hung-Wei
;
Chou, Fu-Hsuan
;
Chang, Yu-Chuan
To develop a drug delivery system (DDS), it is critical to address challenging tasks such as the delivery of hydrophobic and amphiphilic compounds, cell uptake, and the metabolic fate of the drug delivery carrier. Low-density lipoprotein (LDL) has been acknowledged as the human serum transporter of natively abundant lipoparticles such as cholesterol, triacylglycerides, and lipids. Apolipoprotein B (apo B) is the only protein contained in LDL, and possesses a binding moiety for the LDL receptor that can be internalized and degraded naturally by the cell. Therefore, synthetic/reconstituting apoB lipoparticle (rABL) could be an excellent delivery carrier for hydrophobic or amphiphilic materials. Here, we synthesized rABL in vitro, using full-length apoB through a five-step solvent exchange method, and addressed its potential as a DDS. Our rABL exhibited good biocompatibility when evaluated with cytotoxicity and cell metabolic response assays, and was stable during storage in phosphate-buffered saline at 4 degrees C for several months. Furthermore, hydrophobic superparamagnetic iron oxide nanoparticles (SPIONPs) and the anticancer drug M4N (tetra-O-methyl nordihydroguaiaretic acid), used as an imaging enhancer and lipophilic drug model, respectively, were incorporated into the rABL, leading to the formation of SPIONPs- and M4N- containing rABL (SPIO@rABL and M4N@rABL, respectively). Fourier transform infrared spectroscopy suggested that rABL has a similar composition to that of LDL, and successfully incorporated SPIONPs or M4N. SPIO@rABL presented significant hepatic contrast enhancement in T-2-weighted magnetic resonance imaging in BALB/c mice, suggesting its potential application as a medical imaging contrast agent. M4N@rABL could reduce the viability of the cancer cell line A549. Interestingly, we developed solution-phase high-resolution transmission electron microscopy to observe both LDL and SPIO@rABL in the liquid state. In summary, our LDL-based DDS, rABL, has significant potential as a novel DDS for hydrophobic and amphiphilic materials, with good cell internalization properties and metabolicity.
Unsymmetrical Parallel Switched-Capacitor (UP-SC) Regulator with Fast Searching Optimum Ratio Technique
(2017-01-01)
Lin, Yen-Ting
;
Yang, Wen-Hau
;
Ma, Yu-Sheng
;
Lai, Yan-Jiun
;
Chen, Hung-Wei
Different from conventional multiphase switched-capacitor (SC) DC-DC converters, the proposed unsymmetrical parallel switched-capacitor (UP-SC) regulator provides more controllable input variables to increase available conversion ratios for improved load regulation. Even under higher conversion ratio numbers, the UP-SC regulator uses the fast searching optimum ratio (FSOR) technique to search the destined ratio rapidly and to reduce the transient recovery time. Experimental results show the test chip fabricated in 0.25 mu m CMOS process increases the ratio number to 187 and 2389 in 3-stage and 4-stage SC regulators, respectively. Transient recovery time reduces from 26 mu s to 1.5 mu s in case of 7mA load current step.