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1.
大功率开关电源的设计与实现   总被引:3,自引:0,他引:3  
瞿世尊  王可亮  陈健 《电子工程师》2004,30(4):38-40,43
介绍了开关电源设计中需要考虑的几个基本问题,包括频率的确定、最大占孔比Dm的确定、逆变变压器的设计和开关功率管的选择,并以一种1 kW的PWM大功率半桥式开关电源为例,详细介绍实际的开关电源设计方案,并给出了实验结果.  相似文献   
2.
提出了一种用于数字电视发射机中的大功率射频功放模块的设计方案,采用平衡型放大器结构,以LDMOS器件作为功放管,给出了包括射频放大电路和直流馈电电路的实现方法,并提供了对系统增益及线性度等指标的仿真和测试结果.  相似文献   
3.
介绍了一种带USB接口的光的155Mb/s码型发生器。伪随机码和其他格式的码型由PC产生通过USB接口进入双口RAM,再经串并变换后由光发射模块发射。该系统可方便地设定各种格式的码型,并同时具备光接口和电接口,可广泛应用于光通信各种实验中,具有重要的实用价值。  相似文献   
4.
金永镐  陈玲玲 《电子科技》2010,23(2):79-81,97
提出了一种基于偏置模式的热电偶用V—PWM转换器的设计方法和应用电路。这种方式的转换器,可同时完成对微弱电压的积分方式放大及脉宽调制,且具有抗干扰性能优越、放大倍数高、转换精度高、线路简单等特点。特别适用于输出电压很微弱的热电偶温度传感器;结合AT89C2051单片机,可设计出性能稳定、电路简单、成本低且可检测0~1000℃的宽范围温度控制器。  相似文献   
5.
绝缘栅双极型晶体管(IGBT)驱动电路的设计是保证系统可靠运行的重要环节。文中基于英飞凌的磁隔离驱动芯片2ED020I12-F2进行IGBT驱动电路的设计,对2ED020I12-F2的工作过程进行了分析,研究了芯片对IGBT的开通关断及过压过流保护等的工作原理。并运用2ED020I12-F2及其他器件设计了带有变压器隔离与自给电源功能的IGBT驱动电路,且通过实际试验证明了驱动电路设计的正确性与可靠性。  相似文献   
6.
Design and Evaluation of Adiabatic Arithmetic Units   总被引:1,自引:0,他引:1  
Adiabatic design is an attractive approach to reducingenergy consumption in VLSI circuits after exhausting the potentialof conventional energy-saving techniques. Despite the plethoraof adiabatic logic architectures that have been proposed in recentyears, several practical considerations in the design of nontrivialadiabatic circuits remain largely unexplored. Moreover, it isstill unclear whether adiabatic circuits of significant sizeand complexity can achieve substantial savings in energy dissipationover corresponding conventional designs. We recently designedseveral low-power arithmetic units using a dual-rail adiabaticlogic design style. We also designed static CMOS versions ofthese units and compared their energy dissipation with theircorresponding adiabatic designs. In this paper we describe ourimplementations, discuss architecture and logic-level issuesrelated to our adiabatic designs, and present the findings ofour empirical comparison. Our results suggest that adiabaticlogic can be used for the implementation of relatively complexVLSI circuits that dissipate significantly less energy than theircorresponding CMOS designs.  相似文献   
7.
射频芯片内DCXO的晶体振荡主电路设计   总被引:1,自引:0,他引:1  
描述了一种射频芯片内数控晶体振荡器(DCXO)的振荡主电路设计,以Deep-N-Well CMOS工艺的PMOS为主工作管,采用Santos(改进Colpitts)结构、非对称差分式振幅控制环,避免了因Vt依赖工艺与温度等而产生的可靠启振问题.该10MHz DCXO振荡器主电路,采用TSMC Mixed/RF 0.18μm CMOS工艺,在2V电源电压下,仿真得到输出特性为:振幅峰峰值0.8V,平均电流2.9mA,相位噪声-140dBc/Hz@1kHz,-173dBc/Hz@1MHz,启动时间约2.8毫秒,可作为DCXO核心振荡模块.  相似文献   
8.
Direct additive fabrication of thin‐film electronics using a high‐mobility, wide‐bandgap amorphous oxide semiconductor (AOS) can pave the way for integration of efficient power circuits with digital electronics. For power rectifiers, vertical thin‐film diodes (V‐TFDs) offer superior efficiency and higher frequency operation compared to lateral thin‐film transistors (TFTs). However, the AOS V‐TFDs reported so far require additional fabrication steps and generally suffer from low voltage handling capability. Here, these challenges are overcome by exploiting in situ reactions of molybdenum (Mo) during the solution‐process deposition of amorphous zinc tin oxide film. The oxidation of Mo forms the rectifying contact of the V‐TFD, while the simultaneous diffusion of Mo increases the diode's voltage range of operation. The resulting V‐TFDs are demonstrated in a full‐wave rectifier for wireless energy harvesting from a commercial radio‐frequency identification reader. Finally, by using the same Mo film for V‐TFD rectifying contacts and TFT gate electrodes, this process allows simultaneous fabrication of both devices without any additional steps. The integration of TFTs alongside V‐TFDs opens a new fabrication route for future low‐cost and large‐area thin‐film circuitry with embedded power management.  相似文献   
9.
In this work, a method for the rapid synthesis of metallic microtracks on polyetherimide is presented. The method relies on the photosynthesis of silver nanoparticles on the surface of the polymer substrates from photosensitive silver chloride (AgCl), which is synthesized directly on the polyetherimide surface. The study reveals that the use of AgCl as a photosensitive intermediate accelerates the reactions leading to the formation of silver nanoparticles by up to two orders of magnitude faster than other photodecomposition schemes. The patterning can be conducted under blue light, with notable advantages over UV exposure. Polymers of significant interest to the microelectronics and 3D printing industries can be directly patterned by light using this photography‐inspired technique at throughputs high enough to be commercially advantageous. Light exposures as short as a few seconds are sufficient to allow the direct metallization of the illuminated polyetherimide surface. The results show that the silver required for the seed layer is minimal, and the later copper electroless plating results in the selective growth of conductive tracks for circuitry on the light‐patterned areas, both on flexible films and 3D printed surfaces.  相似文献   
10.
High‐rate capability has become an important feature for energy storage devices, but it is often accompanied with a significant reduction in energy density. Therefore, developing an energy storage technology that combines high‐rate capability with high energy density is a great challenge for next‐generation electronic devices. Here, parallel circuitry is constructed at the nanoscale to lower the resistance for ion and electron transport that largely determines the rate performance. The parallel circuitry is constructed through intertwining continuous carbon nanotubes with an interpenetrating conductive assembly based on hierarchically layered MXene (Ti3C2Tx ) functionalized by KMnO4 (MnOx @Ti3C2Tx ). The assembly shows ultrafast rate capability, e.g., maintaining 50% capacity when the current density increases from 0.1 to 10 A g?1. Investigations of the kinetics and charge storage mechanisms confirm the efficiency of the designed parallel circuitry in improving rate capability by providing rapid pathways for ions and electrons, as well as dividing the current flow evenly into individual MnOx @Ti3C2Tx flakes in the assembly. The flexible MnOx @Ti3C2Tx based electrode endows zinc ion batteries with outstanding mechanical robustness and good power delivering performance. The paradigm presented here paves a new way for designing electrodes with high‐rate capability toward next‐generation energy storage technologies.  相似文献   
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