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1.
介绍了一种全新的FM调制器结构.该调制器基于小数分频锁相环技术,并在电荷泵单元中引入额外偏差电流消除电荷泵失配对带内噪声的影响.该芯片采用CSMC 0.5μm DPTM CMOS工艺,测试结果表明,其SNR≥82dB,THD≤0.08,最大带外辐射能量低于-90dBc/Hz.此外,该芯片还采用自动频率调整的方法避免调节片外电感.该芯片的这些特点十分适合调频发射的要求.  相似文献   

2.
介绍了一种应用于433/868MHz频段短距离器件的分数分频频率综合器.采用带自适应频率校准的宽带压控振荡器来覆盖要求的频段,并采用3位量化、3阶的Σ△调制器来实现分数分频和改善锁相环的带外噪声.测试结果表明,自适应频率校准能够正常工作,压控振荡器的频率调节范围为1.31~1.18GHz,在3MHz频偏处的带外噪声为-139dBc/Hz,分数毛刺低于-60dBc.芯片采用0.35μm CMOS工艺,芯片面积仅为1.8mm2,功耗仅为57mW.  相似文献   

3.
为了实现对带外量化噪声进行有效抑制,基于对电荷泵(CP)电流不匹配引起的△-∑量化噪声建模,该文提出一种新型小数分频频率合成器(Frac-N)模型。该模型是在传统小数分频频率合成器的反馈之路上嵌入一个噪声滤除器(NF),该噪声滤除器是由一个不含分频器的宽频带锁相环(PLL)构成。采用该噪声滤除技术不但可以对高阶△-∑调制器(DSM)产生的带外相位噪声进行抑制,还可以减小由于电荷泵(CP)不匹配引起的量化噪声。仿真结果验证了该方法的有效性。  相似文献   

4.
采用Σ△调制技术的小数分频频率合成器设计了CPFSK调制电路,对调制电路的原理以及噪声性能进行了细致的分析.芯片集成了2RC波形成形电路、三阶单级Σ△调制器、双模分频器、鉴频鉴相器、电荷泵和压控振荡器,在四电平2RC-CP FSK调制时,16 kHz的带宽内可以实现25.6 kbps的信息速率传输.电路采用0.35μm标准CMOS工艺实现,调节片外电感,芯片最高工作频率可以到200 MHz.  相似文献   

5.
为了防止在液晶显示面板上发生闪烁和减小栅驱动器的馈通现象,设计了一种基于升压型DC-DC和电荷泵的用于TFT-LCD液品显示的片内门宽调制控制器.该控制器能减小液品显示功耗,减少栅走线和液晶面板之间的耦合效应,其输出延时可调并输入到栅驱动器中,从而避免液晶显示设备错误的显示.采用该门宽调制器的基于电流模PWM升压型DC-DC和电荷泵的芯片已在UMC 0.6μm BCD工艺线投片,DC-DC的效率高达93%,可调电荷泵输出电压为10~30V,测试结果证明该门宽调制控制器电路工作良好,其面积为0.3mm2,静态电流小于1μA.  相似文献   

6.
为了防止在液晶显示面板上发生闪烁和减小栅驱动器的馈通现象,设计了一种基于升压型DC-DC和电荷泵的用于TFT-LCD液品显示的片内门宽调制控制器.该控制器能减小液品显示功耗,减少栅走线和液晶面板之间的耦合效应,其输出延时可调并输入到栅驱动器中,从而避免液晶显示设备错误的显示.采用该门宽调制器的基于电流模PWM升压型DC-DC和电荷泵的芯片已在UMC 0.6μm BCD工艺线投片,DC-DC的效率高达93%,可调电荷泵输出电压为10~30V,测试结果证明该门宽调制控制器电路工作良好,其面积为0.3mm2,静态电流小于1μA.  相似文献   

7.
提出了一种满足ISO/IEC18000-6C标准的无源超高频RFID(射频识别)标签芯片的射频前端结构,该结构包括高效率电荷泵、解调器、调制器、阻抗匹配网络和ESD保护电路。电荷泵通过阈值补偿原理及精确控制补偿电压有效抑制反向漏电流,消除了传统电荷泵中的阈值损失。芯片经TSMC0.18μm CMOS mixed signal工艺流片,实测结果表明,标签最远读距离达7m,写距离为3m,可应用于识别与定位,同时满足HBM2 000V的抗静电指标。  相似文献   

8.
采用ΣΔ调制技术的小数分频频率合成器设计了CPFSK调制电路,对调制电路的原理以及噪声性能进行了细致的分析。芯片集成了2RC波形成形电路、三阶单级ΣΔ调制器、双模分频器、鉴频鉴相器、电荷泵和压控振荡器,在四电平2RC-CPFSK调制时,16kHz的带宽内可以实现25.6kbps的信息速率传输。电路采用0.35μm标准CMOS工艺实现,调节片外电感,芯片最高工作频率可以到200MHz。  相似文献   

9.
介绍了一种适用于数字音频应用的16位8 kHz Σ-Δ调制器,该电路采用单环三阶、单比特量化形式;为适应较低电压,采用带密勒补偿的两级运放.仿真结果显示,调制器在128倍过采样率时,带内信号信噪比可达到102.6.该电路采用UMC 0.18 μm混合信号工艺实现,工作电压为1.8 V,芯片版图面积为1.3 mm×1.3 mm.  相似文献   

10.
介绍了一种适用于数字音频应用的16位8 kHz Σ-Δ调制器,该电路采用单环三阶、单比特量化形式;为适应较低电压,采用带密勒补偿的两级运放.仿真结果显示,调制器在128倍过采样率时,带内信号信噪比可达到102.6.该电路采用UMC 0.18 μm混合信号工艺实现,工作电压为1.8 V,芯片版图面积为1.3 mm×1.3 mm.  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
Call for Papers     
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   

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