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LM12是美国NS公司产品,它具有输出功率大(4Ω负载时正弦波输出功率达150W),失真度低(0.01%),功率带宽宽(60kHz),过载能力强(峰值功率达800W),输出端允许接容性、感性负载,有输入、过压、过流、动态安全区保护等优点,可广泛用于电源、高压稳压器、音频功率放大器、磁头定位仪、X—Y记录仪及伺服控 相似文献
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<正> TPA2013D1是美国德州仪器公司的新产品。这是一种音频D类恒定功率输出的单声道集成电路。其显著的特点就有:1、内置高效(超过90%)升压转换电路,使输出的音频功率不受电源电压下降的影响。工作电源电压范围宽达1.8V~5.5V,使用3.6V电源电压、8Ω扬声器时音频输出功率为2.2W;4Ω扬声器时为 相似文献
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本文介绍一款能驱动阻抗低至1Ω的扬声器音频功率放大器。该机为了具备输出大电流的能力,使用了640VA的大型电源变压器,输出级采用了导通电阻小的大电流MOS—FET的并联推挽电路和大型散热片。为了改善音质,在输入级电路和第二级电路中使用了稳压效果比串联调整稳压电路更好的并联调整稳压电路,整个电路只需引入少量的负反馈即可做到失真很小。在保护电路方面采用了电压检测式扬声器保护电路。该机在1Ω扬声器上的输出功率可达123W。8Ω负载时输出18W。 相似文献
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一般家用Hi-Fi功放大都使用对称供电的±60~150V直流电源电压,但在一般小型汽车上却只能用车上的12V(当车上电池充满电时则是14.4V)单端直流电源为汽车功放供电。大家知道,功放输出功率愈大,所需电源电压愈高。计算结果表明,在12V单端电源电压和4Ω负载下,无变压器推挽功放的最大输出功率只有6W,即使采用桥式输出电路,最大也只能输出20W。因此,要在12V电源电压下设计一台输出功率大于20W的功放一直是一个令人头痛的难题。过去,解决 相似文献
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设计实现了一种用于D类音频功率放大器中的自动增益控制系统,通过自动调整D类功放的增益,增大了D类音频功放的输入信号范围,避免了削波失真,使得D类音频功放能够在较宽信号输入范围内保持良好的总谐波失真(THD),且不影响输出功率.该集成了自动增益控制系统的2.5 W单声道D类音频功放已经采用0.5 μm CMOS工艺实现.测试表明,在电源电压5 V、功放增益18 dB、负载4 Q的条件下,访D类音频功放能够在0~2.3 Vrms的信号输入范围内保持总谐波失真加噪声(THD+N)<2%,最大输出功率2.1 W. 相似文献
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Michael Reilly 《半导体技术》2004,29(12)
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system. 相似文献
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Thomas M.Trexler 《半导体技术》2004,29(5)
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test. 相似文献
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The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high. 相似文献
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The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation. 相似文献
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Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible. 相似文献
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Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's. 相似文献
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It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory. 相似文献
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Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it. 相似文献
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A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working. 相似文献
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《中国通信》2014,(7)
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks 相似文献