关于机械数控加工过程中刀具的合理使用控制与研究

在越来越追求高效率、低制造成本的今天,各行各业都在研究各种先进工艺以提高生产效率并获取更大的利润。本文就数控加工过程中对刀具的合理使用为研究课题,从切削原理、刀具研磨、过程控制、实验论证等几方面进行简单剖析,希望能达到与业界同仁学用互进的目的与效果！     

Fast locking,startup-circuit free,low area, 32-phase analog DLL

This work presents 32-phase analog delay-locked-loop (DLL) having fast locking ability, startup-circuit free operation, and a low area with improved DNL-INL performance. The proposed faster delay-cell and the new bias-circuit enable startup-circuit free operation under process-voltage-temperature (PVT) variation, while the DLL achieves low area and faster locking by using a small filter capacitor. Again, input and output clocks pass through the respective CMOS buffer before the phase detector (PD) for load matching, which reduces DNL-INL in the DLL. The analog DLL locks in less than 54 or 56 clock cycles depending upon initial control voltage (supply or ground voltage) with 100 MHz input clock. The DLL generates 32-phase clocks with a bin-size of 312.5 ps, the peak-to-peak period jitter of 9.51 ps, the rms period jitter of 1.36 ps, the phase-offset error of 4.72 ps, DNL and INL less than ±0.11 LSB. The design consumes 3.54 mW power with a supply voltage of 3.3 V, and an area of 0.017 mm² in UMC 180 nm MMRF technology. ^© 2001 Elsevier Science. All rights reserved     

IC制造中的危害和预防

本文论述了关于IC制造中使用的工艺气体和厂房设施、生产设备的危害及防护。     

Designing soft-edge flip-flop-based linear pipelines operating in multiple supply voltage regimes

Soft-edge flip-flop (SEFF) based pipelines can improve the performance and energy efficiency of circuits operating in the super-threshold (supply voltage) regime by enabling the opportunistic time borrowing. The application of this technique to the near-threshold regime of operation, however, faces a significant challenge due to large circuit parameter variations that result from manufacturing process imperfections. In particular, delay lines in SEFFs have to be over-designed to provide larger transparency windows to overcome the variation in path delays, which causes them to consume more power. To address this issue, this paper presents a novel way of designing delay lines in SEFFs to have a large enough transparency window size and low power consumption. Two types of linear pipeline design problems using the SEFFs are formulated and solved: (1) designing energy-delay optimal pipelines for the general usage that requires SEFFs to operate in both the near-threshold and super-threshold regimes, and (2) designing minimum energy consumed pipelines for particular use case with a minimum operating frequency constraint. Design methods are presented to derive requisite pipeline design parameters (i.e., depth and sizing of delay lines in SEFFs) and operating conditions (i.e., supply voltage and operating frequency of the design) in presence of process-induced variations. HSPICE simulation results using ISCAS benchmarks demonstrate the efficacy of the presented design methods.     

集成电路工艺模拟软件SSUPREM4的校验

本文对知名的集成电路工艺模拟软件ＳＳＵＰＲＥＭ４进行了较仔细的校验,用ＳＳＵＰＲＥＭ４模拟了氧化、扩散工艺,并同实验值进行了比较,模拟值和实验值的偏差在１０％以内,与集成电路器件模拟软件Ｓ－ＰＩＳＣＥＳ联用校验了ＳＳＵＰＲＥＭ４的工序模拟结果,校验结果有较大参考价值。     

飞秒激光钻孔

概述了飞（10^-15）秒级激光钻孔的特征与优点,采用飞（10^-15）秒级激光钻孔可得到无“热影响区”的精细孔,其孔壁平均粗糙度Ra≤0．1μm,位置度≤1％,飞（10^-15）秒级激光技术在PCB行业、汽车工业和航空航天工业等有着广阔的用途。     

再流焊接设备性能评估方法

再流焊接工艺是电子组装三大工序之一,其工艺的精确性直接决定了产品焊接质量。但由于再流焊接工艺的不可视化,使其成为工艺控制的难点。参考IPC-9853标准可对再流焊设备及工艺进行科学的量化评估,使其透明可视化,有助于工艺优化及控制。     

NS2扩展突发性业务流：设计与实现

结合Markov调制泊松过程（MMPP）和混合泊松流,为突发性分组业务设计了Gamma调制泊松过程（GMPP）业务流模型。面向开源仿真器NS2的功能扩展,给出了纯泊松流、MMPP流和GMPP流的NS2扩展设计和实现方案,并经仿真实验进行了验证。分析表明GMPP更适用于实际业务流。     

Efficient recursive least squares parameter estimation algorithm for accurate nanoCMOS variable gain amplifier performances

ABSTRACT

With the aggressive scaling of integrated circuit technology, parametric estimation is a critical task for designers who looked for solutions to the challenges of some Nanoscale CMOS parameters. This paper presented the prediction of primary parameters of CMOS transistor for 16 nm to 10 nm process nodes using both of Bisquare Weights (BW) method and a novel recursive least squares (RLS) parameter estimation algorithm. The proposed RLS algorithm consists of the minimisation of a quadratic criterion relating to the prediction error in order to attain the best estimated parameters of the developed mathematical model. The obtained results thanks to the proposed RLS algorithm were better than those reached using the BW method. Comparisons between Predictive Technology Model (PTM) data and parameters estimated with RLS algorithm were made to check the validity and the consistency of the proposed algorithm. These predicted primary parameters were helpful to estimate and to optimise the performances of the Variable Gain Amplifier (VGA) which was a basic circuit element with a key role in the design of new upcoming receivers.     

基于6S管理理念创新电子工艺实训

电子工艺实训是专业性、操作性要求很高的实训课程,形成良好的职业素养有助于学生未来的就业。电子工艺实训中创新实训模式、改革成绩评价体系,进行有效的6S管理是非常有价值的。根据企业的岗位要求对电子工艺实训各环节内容进行重构,在强化学生实践操作能力的同时,通过潜移默化的方式培养学生的职业素养,将该课程的实训效果发挥到最大。