全文获取类型
收费全文 | 2849篇 |
免费 | 302篇 |
国内免费 | 638篇 |
专业分类
电工技术 | 216篇 |
综合类 | 119篇 |
化学工业 | 11篇 |
金属工艺 | 8篇 |
机械仪表 | 95篇 |
建筑科学 | 2篇 |
矿业工程 | 10篇 |
能源动力 | 3篇 |
轻工业 | 3篇 |
水利工程 | 1篇 |
石油天然气 | 4篇 |
武器工业 | 5篇 |
无线电 | 2755篇 |
一般工业技术 | 115篇 |
冶金工业 | 2篇 |
原子能技术 | 53篇 |
自动化技术 | 387篇 |
出版年
2024年 | 5篇 |
2023年 | 18篇 |
2022年 | 14篇 |
2021年 | 36篇 |
2020年 | 52篇 |
2019年 | 37篇 |
2018年 | 45篇 |
2017年 | 72篇 |
2016年 | 96篇 |
2015年 | 119篇 |
2014年 | 178篇 |
2013年 | 207篇 |
2012年 | 146篇 |
2011年 | 266篇 |
2010年 | 227篇 |
2009年 | 253篇 |
2008年 | 325篇 |
2007年 | 293篇 |
2006年 | 284篇 |
2005年 | 210篇 |
2004年 | 197篇 |
2003年 | 147篇 |
2002年 | 132篇 |
2001年 | 94篇 |
2000年 | 85篇 |
1999年 | 53篇 |
1998年 | 30篇 |
1997年 | 29篇 |
1996年 | 30篇 |
1995年 | 29篇 |
1994年 | 14篇 |
1993年 | 13篇 |
1992年 | 16篇 |
1991年 | 11篇 |
1990年 | 9篇 |
1989年 | 2篇 |
1988年 | 10篇 |
1987年 | 1篇 |
1984年 | 2篇 |
1983年 | 2篇 |
排序方式: 共有3789条查询结果,搜索用时 187 毫秒
1.
针对高帧频、全局曝光和光谱平坦等成像应用需求,设计了一款高光谱成像用CMOS图像传感器。其光敏元采用PN型光电二极管,读出电路采用5T像素结构。采用列读出电路以及高速多通道模拟信号并行读出的设计方案来获得低像素固定图像噪声(FPN)和非均匀性抑制。芯片采用ASMC 0.35μm三层金属两层多晶硅标准CMOS工艺流片,为了抑制光电二极管的光谱干涉效应,后续进行了光谱平坦化VAE特殊工艺,并对器件的光电性能进行了测试评估。电路测试结果符合理论设计预期,成像效果良好,像素具备积分可调和全局快门功能,最终实现的像素规模为512×256,像元尺寸为30μm×30μm,最大满阱电子为400 ke^(-),FPN小于0.2%,动态范围为72 dB,帧频为450 f/s,相邻10 nm波段范围内量子效率相差小于10%,可满足高光谱成像系统对CMOS成像器件的要求。 相似文献
2.
This paper presents a physics-based compact gate delay model that includes all short-channel phenomena prevalent at the ultra-deep submicron technology node of 32 nm. To simplify calculations, the proposed model is connected to a compact α-power law-based (Sakurai-Newton) model. The model has been tested on a wide range of supply voltages. The model accurately predicts nominal delays and the delays under process variations. It has been shown that at lower technology nodes, the delay is more sensitive to threshold voltage variations, specifically at the sub-threshold operating region as compared with effective channel length variations above the threshold region. 相似文献
3.
Analog integrated circuit design has as integral parts both analytical reasoning and numerical validation in the process from topology construction to sizing. Given a circuit topology, different circuit sizing results can be obtained from different processes of sizing inference. Sizing methods by simulation-based numerical searching have been a continuously studied subject. However, almost all approaches in this category require an overwhelming number of circuit simulations to arrive at an optimized sizing result. On the other hand, many published manual sizing methods by using the conventional device equations also require repeated SPICE simulations to correct the equation-based sizing results. This paper proposes a systematic gm/ID-based initial sizing method specifically customized for designing multiple-stage operational amplifiers (Op Amps). A main feature of the proposal is to use circuit-level design equations as constraints on the gm/ID table lookup method to substantially reduce the uncertainty in the sizing calculations. As a result, a significant amount of SPICE based correction work can be reduced to complete an initial sizing. The proposed sizing procedure includes a few regular sizing rules customized to the configuration of multi-stage Op Amps. We validate the proposed sizing method by application to several multi-stage Op Amp examples with a capacitive load or Miller compensation. Simulations have justified that the produced initial sizing results can achieve most of the prespecified design targets. 相似文献
4.
Yo-Sheng Lin Kai-Siang Lan Ming-Yuan Chuang Yu-Ching Lin 《International Journal of Electronics》2018,105(6):1063-1077
This paper reports a 94 GHz CMOS voltage-controlled oscillator (VCO) using both the negative capacitance (NC) technique and series-peaking output power and phase noise (PN) enhancement technique. NC is achieved by adding two variable LC networks to the source nodes of the active circuit of the VCO. NMOSFET varicaps are adopted as the required capacitors of the LC networks. In comparison with the conventional one, the proposed active circuit substantially decreases the input capacitance (Cin) to zero or even a negative value. This leads to operation (or oscillation) frequency (OF) increase and tuning range (TR) enhancement of the VCO. The VCO dissipates 8.3 mW at 1 V supply. The measured TR of the VCO is 91~96 GHz, close to the simulated (92.1~96.7 GHz) and the calculated one (92.2~98.2 GHz). In addition, at 1 MHz offset from 95.16 GHz, the VCO attains an excellent PN of – 98.3 dBc/Hz. This leads to a figure-of-merit (FOM) of ?188.5 dBc/Hz, a remarkable result for a V- or W-band CMOS VCO. The chip size of the VCO is 0.75 × 0.42 mm2, i.e. 0.315 mm2. 相似文献
5.
This paper introduces a 9-bit time-based capacitance-to-digital converter (T-CDC). This T-CDC adopts a new design methodology for parasitic cancellation with a simple calibration technique. In T-CDCs, the input sensor capacitance is first converted into a delay pulse using a capacitance-to-time converter (CTC) circuit; then this delay signal is converted into a digital code through a time-to-digital converter (TDC) circuit. A prototype of the proposed T-CDC is implemented in UMC 0.13 μm CMOS technology. This T-CDC consumes 8.42 μW and achieves a maximum SNR of 45.14 dB with a conversion time of 1 μs that corresponds to a figure of merit (FoM) of 16.4 fJ/Conv. 相似文献
6.
《Microelectronics Reliability》2015,55(11):2229-2235
In these decades, integrated circuits for biomedical electronics applications have been designed and implemented in CMOS technologies. In order to be safely used by human, all microelectronic products must meet the reliability specifications. Therefore, electrostatic discharge (ESD) must be taken into consideration. To protect the biomedical integrated circuits in CMOS technologies from ESD damage, a dual-directional silicon-controlled rectifier (DDSCR) device was presented in this work. Experimental results show that the DDSCR has the advantages of high ESD robustness, low leakage, large swing tolerance, and good latchup immunity. The DDSCR was suitable for ESD protection in biomedical integrated circuits. 相似文献
7.
提出了一种低电压高增益CMOS下变频混频器的新结构.这个结构避免了堆叠晶体管,因此可以在低电压下工作.在LO信号的频率为1.452GHz,RF信号频率为1.45GHz的情况下,仿真结果表明:混频器的增益为15dB,ⅡP3为-4.5dBm,NF为17dB,最大瞬态功耗为9.3mW,直流功耗为9.2mW.并对该混频器的噪声特性和线性度进行了分析. 相似文献
8.
9.
10.