彩色显示器与彩色电视机电路对比

<正> 众所周知,显示器是计算机维修中占维修比率最高的部件,因为显示器和电视机类似,属于大功率发热设备,鉴于显示器在整个计算机中所占的成本,不可能在其损坏时随时更换,这使得彩色显示器维修的社会需求量很大,但目前无论是原装机、品牌机和各种组装兼容机在购买时都不提供显示器     

交通灯控制器数字电路的设计及仿真

本文针对十字路口的交通灯控制器及其数字显示功能进行设计。控制部分以同步十进制计数器为控制芯片构成模拟8进制计数器及BCD码显示器构成的显示电路组成;受控部分即A街道、B街道共计六盏灯。在完成电路设计的基础上采用Multisim仿真软件实现对电路功能的仿真。     

基于集成计数器的N进制计数器设计与仿真

计数器是一种重要的时序逻辑电路,广泛应用于各类数字系统中。介绍以集成计数器74LS161和74LS160为基础,用归零法设计N进制计数器的原理与步骤。用此方法设计了3种36进制计数器,并用Multisim10软件进行仿真。计算机仿真结果表明设计的计数器实现了36进制计数的功能。基于集成计数器的N进制计数器设计方法简单、可行,运用Multisim 10进行电子电路设计和仿真具有省时、低成本、高效率的优越性。     

任意进制计数器设计方法

利用集成二、十进制计数器采用反馈置数法设计任意进制计数器,已有设计方法的特点是采用一次置数。提出了采用多次置数法设计任意进制计数器的新概念,通过状态转换图分析论述了设计依据,以设计实例说明了采用多次置数设计任意进制计数器的方法。分析与设计举例表明该设计方法是可行的,它拓宽了采用MSI设计任意进制计数器的途径。     

基于Protues的任意N进制计数器的设计与仿真

用集成计数器芯片设计任意N进制计数器是数字电路教学中的一个难点,其原因一是集成计数器芯片种类繁多;二是集成计数器芯片的清零、置数端采用同步或异步方式清零或置数,其清零或置数的方式不同采用的清零或置数的函数也不同。采用仿真方式构成任意进制计数器,可以非常直观的将电路和输出状态、输出波形展现在屏幕上,使学生有一个直观的映像。可以加深学生的理解,提高教学效率,取得事半功倍的效果。     

基于激励函数修改技术的任意进制计数器设计

在推导用T触发器构成的二进制同步加减法计数器的设计公式之基础上,提出了用激励函数修改技术设计任意进制计数器的方法,并以十二进制加减法计数器的设计过程为例说明这种设计方法具有设计快捷、快速、方便的优点。     

模N计数器的简易设计

介绍了用标准计数器结合与门电路,构成任意进制计数器的方法,给出了设计实例。     

实达5GIr显示器二次电源及行输出电路原理

目前彩色显示器种类繁多，而生产厂家通常不提供电路原理图。现将较有代表性的实达5GIr型显示器二次电源及行输出电路对照线路板实物画出，如图1所示。并对其电路原理进行分析，以利于对显示器二次电源及行输出电路的故障维修作参考。     

BS7702-D型彩显信号源的性能及应用

<正> 近年来,随着电脑的逐步普及并进入家庭,彩色显示器也为越来越多的消费者所熟悉。在家用电脑的外围设备中,显示器是相对故障率较高的部件。许多人以为,显示器与电视的原理是一样或相似的,维修手段也差不多。其实,两者之间的差异还是很大的。 以往电脑彩显在维修、调试时往往需要与主机连接,尤其是近年来比较盛行的节能型(EPA)显示器必须联机,否则黑屏无任何显示,这样在维修时就不知道是主机故障还是彩显故障。如果家电维修人员未配备电脑主机,将会给维修或调试带来很大麻烦,即使有主机也需相应软件,操作维修也不方便。另外,彩显的彩色失真及白平衡色纯不良,若没有标准的彩色     

同步十进制计数器CT4160及其应用

本文根据置位法和复位法提出了用同步十进制计数器和四位超前进位全加器构成的任意进制计数器。此外，用BCD码十进制计数器和八选一数据选择器还构成了任意码制十进制计数器。     

Temporal quantisation noise

The temporal quantisation process inherent to certain waveform acquisition systems is examined and quantified. It is shown that increasing sample density (oversampling) is markedly more effective than signal averaging in reducing the influence of this impairment and that timebase quantisation resolution requirements usually exceed those for signal amplitude, although signal averaging can ameliorate this situation.     

一种二—五进制计数器的设计与制作

采用ＥＣＬ技术研制了一种二－五进制计数器ＳＥ１６７８。文章主要介绍了该器件的工作原理，版图和工艺设计及器件的性能分析等，最终产品典型工作频率可达５５０ＭＨｚ，最高电路翻转频率可达７５０ＭＨｚ，功耗电流典型值为１２０ｍＡ。     

A low-power correlation-derivative CMOS VLSI circuit for bearing estimation

We present a CMOS integrated circuit (IC) for bearing estimation in the low-audio range that performs a correlation derivative approach in a 0.35-/spl mu/m technology. The IC calculates the bearing angle of a sound source with a mean variance of one degree in a 360/spl deg/ range using four microphones: one pair is used to produce the indication and the other to define the quadrant. An adaptive algorithm decides which pair to use depending on the direction of the incoming signal, in such a way to obtain the best estimate. The IC contains two blocks with 104 stages each. Every stage has a delay unit, a block to reduce the clock speed, and a 10-bit UP/DN counter. The IC measures 2 mm by 2.4 mm, and dissipates 600 /spl mu/W at 3.3 V and 200 kHz. It is purely digital and uses a one-bit quantization of the input signals.     

A low-cost quadrature decoder/counter interface integrated circuit for AC induction motor server control

An AC motor server control IC which performs the quadrature decoder, counter, and bus interface function is presented in this paper. This interface IC employing TSMC 0.6µm SPTM technology has been fabricated and tested and the results indicate that its function fully works. A novel noise filter logic is included in the design which allows reliable operations in noisy environments. It also contains a quadrature decoder such that the phase lag of an external clock and the input signal can be determined.     

Multi-purpose controllable function generator

This paper deals with the design and implementation of a new multi-purpose function generator, in which the frequency of oscillation can be controlled by an external signal. It provides different types of waveforms such as sine, square, triangle, TTL square and monitor waveforms. The TTL square and monitor waveforms are provided for use respectively as a clock to logic circuits and for various timebase applications. The function generator provides low-distortion outputs from 1 MHz to 1 MHz in nine controlled ranges. The output waveforms are calibrated 0-20 V pk-pk with DC offset control. Input and output impedances are 10Ω and 600Ω, respectively.     

基于Electronics Workbench的逻辑电路设计

针对加快电子电路的设计,缩短电子产品的生存周期,提高逻辑判断分析能力及电子设计效率.采用基于EWB仿真软件,结合74191的逻辑功能特点,设计了四位同步二进制可逆计数器.通过EWB仿真软件,从数字逻辑信号分析仪输出的波形来看,实现了对输入脉冲信号进行计数的功能.理论设计方案预期与仿真实验结果基本一致.     

Nonideal Photoelectron Counting

Expressions are obtained for the probability of error of a binary intensity-modulated direct-detection optical communication system consisting of an ideal photodetector followed by a nonideal photoelectron counter, in this case anRClow-pass filter. Calculation of probability of error requires the determination of the output statistics of the nonideal counter. Numerical techniques are used to evaluate the expression for probability of error and optimum thresholds as a function of signal level. The optimum filter bandwidth required to simulate an ideal counter is also evaluated numerically. Results indicate that, for the particular case considered, the nonideal receiver requires an additional 1 dB of signal power to achieve performance equivalent to the ideal receiver.     

Non-binary Sparse Measurement Matrices for Binary Signal Recovery

Binary sparse measurement matrices are widely used in compressed sensing (CS) due to their low computational complexity. However, binary sparse measurement matrices perform well in CS-based binary signal recovery only when the source signals are very sparse (e.g., k/n=0.1, where k is the sparsity of the source signal, n is the length of the source signal). In this paper, we propose to construct a non-binary sparse measurement matrix to recover binary source signals which are not so sparse (e.g., k/n=0.2) accurately with few measurements. The novel measurement matrix enables us to design a suboptimal and effective recovery algorithm by fully exploiting the structural features. Moreover, we analyze and estimate the un-recovery probability based on the tree structure to evaluate the recovery performance. The simulation results validate that non-binary sparse measurement matrices can be used to recover binary source signals which are not so sparse, the recovery performance of non-binary sparse measurement matrices is better than that of binary sparse measurement matrices in terms of the un-recovery probability.     

一种微型激光电源

本文简述了用一块集成电路、一只晶体管、一个变压器,组成每分钟10次的激光电源充电电路及控制电路、距离计数器5V电源的原理.印制板尺寸40mm×50mm左右,全重仅40g.