Structural Fault Based Specification Reduction for Testing Analog Circuits

Specification reduction can reduce test time, consequently, test cost. In this paper, a methodology to reduce specifications during specification testing for analog circuit is proposed and demonstrated. It starts with first deriving relationships between specifications and parameter variations of the circuit-under-test (CUT) and then reduces specifications by considering bounds of parameter variations. A statistical approach by taking into account of circuit fabrication process fluctuation is also employed and the result shows that the specification reduction depends on the testing confidence. A continuous-time state-variable benchmark filter circuit is applied with this methodology to demonstrate the effectiveness of the approach.     

Generation of Technology-Independent Retargetable Analog Blocks

This paper introduces a complete methodology for retargeting of analog cells to different sets of specifications. This methodology is technology-independent, thus allowing the migration, from one technology to another, of the circuit under retargeting. Careful integration of the device sizing and layout generation tasks via the incorporation of layout constraints during the sizing process allows to generate fully functional designs in a few minutes. The methodology is illustrated via the retargeting of a fully-differential Miller-compensated two-stage operational amplifier for a new set of specifications and two different technological processes.An erratum to this article can be found at     

Low-Power Adaptive Biased Integrated Amplifiers

In this paper the author will present the working principle and the applications of a novel adaptive biasing topology, designed to decrease the stand-by power dissipation without affecting the transient performance of low-power amplifiers. The proposed circuit, whose principle and circuit topology can be implemented both in CMOS and in bipolar standard technologies, gives a biasing current whose value depends on the applied input differential voltage and can be set according to the requested transient performance constraints. The adaptive architecture can be utilized in the design of high-efficient low-power operational amplifiers, for the biasing of both the input stage (where the input source current is dynamically increased) and the output stage (where the output current can be controlled and limited). These amplifiers show a very good behaviour, evaluated in terms of two efficiency factors, if compared with those of other adaptive solutions and class-AB topologies, proposed in the literature. Simulation results and also measurements on a chip prototype, fabricated in a standard CMOS technology, are finally presented.     

Windows应用程序的实时性编程技术

针对实时软件所具有的特点,分析了Windows操作系统所提供的多线程、动态优先级、锁定物理内存以及用户编写驱动程序在实时软件的执行过程中起到的关键作用,提出了一种通过有效利用操作系统服务来提高实时软件的实时性的新思路,其可行性和有效性在电荷耦合器件目标综合测量系统中得到了验证,在实时软件与操作系统平台的融合技术上取得了突破.     

基于双积分模拟重构大动态范围CIS系统研究

提出一种采用列共用模拟重构电路和双积分三采样工作时序的CMOS图像传感器(CIS)系统架构,可实现光电响应曲线压缩和像素固定模式噪声(FPN)消除,提高传感器动态范围到83 dB,使成像质量提高.该结构具有与单采样相同的像素阵列,仅增加很小的处理电路.改进的工作时序优化了长积分、短积分和信号处理的时序分配.系统控制由FPGA实现.功能和数模混合仿真验证表明,方案是可行的.     

基于ADS1606的高速、高精度ADC设计

ADS1606是典型的高性能模/数转换器.详细介绍了ADS1606的主要特性、数字部分控制、模拟输入方式选择、参考电压、电源特性、PCB设计要点以及多种控制结构的测试和分析等.同时,利用设计和测试ADS1606的过程,提出一些高性能模/数转换系统的设计经验.     

IPO+FMM混合方法结合GRI和级联技术计算电大腔体的RCS

采用快速方法(FMM, RPFMM, FaFFA)加速迭代物理光学法(IPO)的迭代过程,可以快速计算电大腔体的电磁散射特性。采用广义互易积分,用靠近腔体终端的一个St面将腔体分成两段,形状简单光滑的腔体前端用IPO结合快速算法处理,而腔体终端单独分析。为了能够处理深腔体和进一步加快计算速度,将腔体前端进一步分成几个子腔体,每一个子腔体独立分析,通过一个级联方法求得腔体前端在St面产生的辐射场,最终在St面用广义互易积分求得腔体的RCS。数值计算结果表明该方法是准确的,同时能有效地提高计算速度。     

一种低温漂BiCMOS带隙基准电压源的设计

文章介绍了一种低温漂的BiCMOS带隙基准电压源.基于特许半导体(Chartered)0.35 μm BiCMOS工艺,采用Brokaw带隙基准电压源结构,通过一级温度补偿技术,设计得到了一种在-40℃到 85℃的温度变化范围内温度系数为15.2×10-6/℃,输出电压为2.5 V±0.002 V的带隙基准电压源电路.±20%的电源电压变化情况下,输出电压变化为2.2 mV,电源电压抑制比为60 dB.5 V电源电压下功耗为1.19 mW.具有良好的电源抑制能力.     

标量衍射理论的非傍轴修正

当光束具有较大的发散角或光束束腰可与波长相比拟时,傍轴近似不再成立.用微扰级数法处理非傍轴光束的传播问题,数值计算发现,对受硬边光阑限制的光束,由于高频分量的贡献,当传输距离较大时,高阶级数解的修正效果不好,甚至失效,级数解的有效范围将受到很大限制.在标量衍射理论角谱表示的基础上,以平面波圆孔衍射为例,给出了衍射场的非傍轴修正解,得到的非傍轴修正解避免了级数解本身在数学上的发散性问题,并在一定条件下,可过渡到级数解,并且指出在近场或非傍轴区对傍轴解进行高阶修正的必要性和有效性.     

一种专业音频立体声相位测量仪的设计

根据广播电台和录音棚的相位检测需求,利用模拟乘法器的鉴相功能,设计出一种专业音频立体声相位测量仪,有效避免了音频节目生产过程中的反相问题.