• Title/Summary/Keyword: single-mode operation

Search Result 293, Processing Time 0.027 seconds

A Study on the Characteristics and Programming Conditions of the Scaled SONOSFET NVSM for Flash Memory (플래시메모리를 위한 Scaled SONOSFET NVSM의 프로그래밍 조건과 특성에 관한 연구)

  • 박희정;박승진;남동우;김병철;서광열
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.13 no.11
    • /
    • pp.914-920
    • /
    • 2000
  • When the charge-trap type SONOS(polysilicon-oxide-nitride-oxide-semiconductor) cells are used to flash memory, the tunneling program/erase condition to minimize the generation of interface traps was investigated. SONOSFET NVSM(Nonvolatile Semiconductor Memory) cells were fabricated using 0.35 ㎛ standard memory cell embedded logic process including the ONO cell process, based on retrograde twin-well, single-poly, single metal CMOS(Complementary Metal Oxide Semiconductor) process. The thickness of ONO triple-dielectric for the memory cell is tunnel oxide of 24 $\AA$, nitride of 74 $\AA$, blocking oxide of 25 $\AA$, respectively. The program mode(V$\_$g/=7, 8, 9 V, V$\_$s/=V$\_$d/=-3 V, V$\_$b/=floating) and the erase mode(V$\_$g/=-4, -5, -6 V, V$\_$s/=V$\_$d/=floating, V$\_$b/=3 V) by MFN(Modified Fowler-Nordheim) tunneling were used. The proposed programming condition for the flash memory of SONOSFET NVSM cells showed less degradation(ΔV$\_$th/, S, G$\_$m/) characteristics than channel MFN tunneling operation. Also, the program inhibit conditins of unselected cell for separated source lines NOR-type flash memory application were investigated. we demonstrated that the phenomenon of the program disturb did not occur at source/drain voltage of 1 V∼12 V and gate voltage of -8 V∼4 V.

  • PDF

Surgical Management of Thoracic Empyema.* - 330 cases - (농흉의 외과적 치료330)

  • 김치경
    • Journal of Chest Surgery
    • /
    • v.20 no.1
    • /
    • pp.65-70
    • /
    • 1987
  • Empyema thoracis following pneumonia, pulmonary tuberculosis, trauma and surgical procedures continues to be a source of major morbidity and mortality. We retrospectively reviewed the hospital records of 330 patients [child:87, adult243] treated for empyema thoracis at Catholic Medical Center between 1964 and 1986. The causes of empyema in these patients were as follows: pneumonia [C***:66%, A***:30%], pulmonary tuberculosis [C:2%, A:20%], lung abscess [C:3%, A:5%], postoperative complication [C:0%, A:13%], trauma [C:1%, A:4%] and unknown origin [C:23%, A:17%]. Three patients in this series died of sepsis from necrotizing pneumonia. Staphylococcus [29.3%], Streptococcus [8.8%], E. coli [8%], Mycobacterium tuberculosis [7.9%], Klebsiella [7.4%], Pseudomonas [6.4%], Bacteroides [3.4%] were the organisms most commonly isolated. Bacterial isolates were single in 68.3%, multiple 7.5% and absent 24.2%. The type of organism did not correlate with severity of disease or eventual requirement for closed thoracotomy drainage, open thoracotomy drainage [Modified Eloesser*s procedure], thoracoplasty, decortication or pleuropneumonectomy. Successful methods of treatment included aspiration in 44%, tube thoracotomy in 66%, open thoracotomy drainage in 98.7%, thoracoplasty in 98%, decortication in 96% and pleuropneumonectomy in 73%. Initial mode of management in empyema thoracis are thoracentesis and closed thoracotomy drainage. If the initial management was failed, we performed another surgical procedures. Before 1973, we manage with Schede`s thoracoplasty in the postpneumonectomy empyema patients. But thoracoplasty, with or without the use of muscle flaps, is a hazardous operation in the poor-risk patients. The permanent, open thoracotomy drainage is a relatively minor operation which is well tolerated even by cachexic, septic patients. It controls infection, and sometimes results in the bronchopleural fistula closing spontaneously.

  • PDF

A Novel Switched Capacitor High Step-up dc/dc Converter Using a Coupled Inductor with its Generalized Structure

  • Hamkari, Sajjad;Moradzadeh, Majid;Zamiri, Elyas;Nasir, Mehdi;Hosseini, Seyed Hossein
    • Journal of Power Electronics
    • /
    • v.17 no.3
    • /
    • pp.579-589
    • /
    • 2017
  • In this study a new high step-up dc-dc converter is presented. The operation of the proposed converter is based on the capacitor switching and coupled inductor with a single active power switch in its structure. A passive voltage clamp circuit with two capacitors and two diodes is used in the proposed converter for elevating the converter's voltage gain with the recovered energy of the leakage inductor, and for lowering the voltage stress on the power switch. A switch with a low $R_{DS}$ (on) can be adopted to reduce conduction losses. In the generalized mode of the proposed converter, to reach a desired voltage gain, capacitor stages with parallel charge and series discharge techniques are extended from both sides of secondary side of the coupled inductor. The proposed converter has the ability to alleviate the reverse recovery problem of diodes with circuit parameters. The operating principle and steady-states analyses are discussed in detail. A 40W prototype of the proposed converter is implemented in the laboratory to verify its operation.

The Realization of a Single-Phase Parallel Active Power Filter to Eliminate Harmonics of Source Current Generated by Nonlinear Loads (비선형부하에 의해 발생한 전원 전류의 고조파를 제거하기 위한 단상 병렬형 Active Power Filter의 구현)

  • Jang, Mok-Soon;Lee, Hu-Chan;Kim, Sang-Hoon;Park, Jong-Yeon
    • Proceedings of the KIEE Conference
    • /
    • 2006.07a
    • /
    • pp.220-221
    • /
    • 2006
  • This paper presents a single-phase parallel active power filter with an analog control circuit to eliminate for harmonic source currents generated by nonlinear loads. The proposed system removes the harmonic source currents by injecting a compensation current that is 180' out of phase with the load harmonic current. The detection of the load harmonics is realized by a simple new structure, referred to the Notch Filter with GIC (Generalized Impedance Converter), which has higher Q than existing harmonic detecters and a simpler structure. The compensation current is obtained using the proposed harmonic detection circuit, DC-Link voltage, and output current of the full-bridge inverter controlled current mode PWM controller. The operation of the proposed system is verified experimentally.

  • PDF

A RF Frong-End CMOS Transceiver for 2㎓ Dual-Band Applications

  • Youn, Yong-Sik;Kim, Nam-Soo;Chang, Jae-Hong;Lee, Young-Jae;Yu, Hyun-Kyu
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.2 no.2
    • /
    • pp.147-155
    • /
    • 2002
  • This paper describes RF front-end transceiver chipset for the dual-mode operation of PCS-Korea and IMT-2000. The transceiver chipset has been implemented in a $0.25\mutextrm{m}$ single-poly five-metal CMOS technology. The receiver IC consists of a LNA and a down-mixer, and the transmitter IC integrates an up-mixer. Measurements show that the transceiver chipset covers the wide RF range from 1.8GHz for PCS-Korea to 2.1GHz for IMT-2000. The LNA has 2.8~3.1dB NF, 14~13dB gain and 5~4dBm IIP3. The down mixer has 15.5~16.0dB NF, 15~13dB power conversion gain and 2~0dBm IIP3. The up mixer has 0~2dB power conversion gain and 6~3dBm OIP3. With a single 3.0V power supply, the LNA, down-mixer, and up-mixer consume 6mA, 30mA, and 25mA, respectively.

Soft Switching Boost Converter using a Single Switch (단일 스위치를 사용한 소프트 스위칭 부스트 컨버터)

  • Jung, Doo-Yong;Kim, Jae-Hyeng;Ji, Young-Hyok;Won, Chung-Yuen;Jung, Yong-Chae
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.14 no.3
    • /
    • pp.211-219
    • /
    • 2009
  • In this paper, a detailed analysis of zero current or zero voltage switching boost converter using a single switch is described. The proposed topology is capable of decreasing switching loss of IGBT device using soft switching technique. As a results, it can be reduced size and weight of passive elements. Based on the mode analysis, practical design considerations are presented. We confirm the converter topology, principle of operation and simulation results obtained from the PSIM software. The performance of the proposed converter is verified by with 1kW(400V, 2.5A) prototype circuit operated at 30kHz.

High Power Factor and High Efficiency DC-DC Converter using Single-Pulse Soft-Switching (단일 펄스 소프트 스위칭을 이용한 고역률 고효율 DC-DC 컨버터)

  • Jung, S.H.;Kwon, S.K.;Suh, K.Y.;Lee, H.W.;Gac, D.K.;Kim, Y.C.
    • Proceedings of the KIEE Conference
    • /
    • 2003.07b
    • /
    • pp.1148-1150
    • /
    • 2003
  • Power conversion system must be increased switching frequency in order to achieve a small size, a light weight and a low noise. However, the switches of converter are subjected to high switching power losses and switching stresses. As a result of those, the power system brings on a low efficiency. To improved these, a large number of soft switching topologies included a resonant circuit has been prosed. But these circuits increase number of switch in circuit and complicate sequence of switching operation. In this paper, the authors propose a high power factor and high efficiency DC-DC converter using single-pulse soft switching by partial resonant switching node. The switching devices in a prosed circuit are operated with soft switching by the partial resonant method, that is, Partial Resonant Switch Mode Power Converter. The partial resonant circuit makes use of a inductor using step up and a condenser of loss-less snubber. The result is that the switching loss is very low and the efficiency of system is high. Also the proposed converter is deemed the most suitable for high power applications where the power switching devices are used. Some simulative results on computer results are included to confirm the validity of the analytical results.

  • PDF

A Novel Auxiliary Edge-Resonant Snubber-Assisted Soft Switching PWM High Frequency Inverter with Series Capacitor Compensated Resonant Load for Consumer Induction Heating

  • Ahmed Nabil A.;Iwai Toshiaki;Omori Hideki;Lee Hyun-Woo;Nakaoka Mutsuo
    • Journal of Power Electronics
    • /
    • v.6 no.2
    • /
    • pp.95-103
    • /
    • 2006
  • In this paper, a novel prototype of auxiliary switched capacitor assisted voltage source soft switching PWM Single-Ended Push Pull (SEPP) series capacitor compensated load resonant inverter with two auxiliary edge resonant lossless inductor snubbers is proposed and discussed for small scale consumer high-frequency induction heating (IH) appliances. The operation principle of this inverter is described by using switching mode equivalent circuits. The newly developed multi resonant high-frequency inverter using trench gate IGBTs can regulate its output AC power via constant frequency edge-resonant associated soft switching commutation by using an asymmetrical PWM control or duty cycle control scheme. The brand-new consumer IH products which use the newly proposed edge-resonant soft switching PWM-SEPP type series load resonant high-frequency inverters are evaluated using power regulation characteristics, actual efficiency vs. duty cycle and input power vs. actual efficiency characteristics. Their operating performance compared with some conventional soft switching high-frequency inverters for IH appliances is discussed on the basis of simulation and experimental results. The practical effectiveness of the newly proposed soft switching PWM SEPP series load resonant inverter is verified from an application point of view as being suitable for consumer high-frequency IH appliances.

Single-Phase Utility-Interactive Inverter for Residential Fuel Cell Generation System (가정용 연료전지 발전 시스템을 위한 단상 계통연계형 인버터)

  • Jung, Sang-Min;Bae, Young-Sang;Yu, Tae-Sik;Kim, Hyo-Sung;Choi, Se-Wan
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.12 no.1
    • /
    • pp.81-88
    • /
    • 2007
  • In this paper, a new single-phase utility-interactive inverter system for residential power generation with fuel cell is proposed. The proposed inverter system is not only capable of working in both stand-alone and grid-connected mode, but also ensures smooth and automatic transfer between the two modes of operation. The proposed control method has little steady-state error and good transient response characteristic. Also, the control method can be implemented using low-cost, fixed point DSP since it has simpler structure, smaller amount of calculation, and smaller number of sensors. The controller for the proposed utility-interactive inverter system is described, and the validity is verified through simulation and experiment.

The Study of Single Phase Source Stability consider for The DSC Cell's Operation Character by Controlled Feed-back Circuit

  • Lee, Hee-Chang
    • Journal of information and communication convergence engineering
    • /
    • v.4 no.4
    • /
    • pp.170-173
    • /
    • 2006
  • Recently, with increasing efficiency of DSC (photo-electrochemical using a nano-particle), The Performance of DSC solar generation system also needs improvement. The approach consists of a Fly-back DC-DC (transfer ratio 1:10) converter to boost the DSC cell voltage to 300VDC. The four switch (MOSFET) inverter is employed to produce 220V, 60Hz AC outputs. High performance, easy manufacturability, lower component count., safety and cost are addressed. Protection and diagnostic features form an important part of the design. Another highlight of the proposed design is the control strategy, which allows the inverter to adapt to the: requirements of the load as well as the power source. A unique aspect of the design is the use of the DSP TMS320LF2406 to control the inverter by current and voltage feed-back. Efficient and smooth control of the: power drawn from the DSC Cell is achieved by controlling the front end DC-DC converter in current mode.