摘要
4位双向移位寄存器74194在时钟脉冲CP=0期间,模式选择信号S1S0的状态变化可能造成逻辑功能混乱。利用ISPLEVER Starter Software2.0软件设计的测试向量文件,对74194进行仿真,仿真波形证明存在这种现象。通过对产生上述问题的原因分析,表明在CP=0期间,S1S0状态的变化,会使74194内部触发器的时钟脉冲输入端出现错误的脉冲信号。最后给出了解决此问题的建议。
Four - bit bidirectional shift - register 74194 during clock pulse CP = 0, the change of state of a two - bit mode - select code S1S0 ,may cause confusion of logical function. Making use of ISPLEVER Starter Software2.0 to design test vector for 74194 simulaing,simulating wave show that there is the phenomenon. By analysing the reason which caused the problem, indicates the change of state of a two - bit mode -select code S1S0 during clock pulse CP= 0, would appear wrong pulse at the clock input of flip- flop of 74194, finally,put forward the means to solve the problem.
出处
《现代电子技术》
2006年第16期143-144,共2页
Modern Electronics Technique
关键词
集成电路
移位寄存器
功能分析
模式选择信号
integrated circuit
shift - register
function analysis
mode - select signal
