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Need help with Simulink "Memory" block.
Posted:
Nov 16, 1996 12:59 PM


I am trying to use Simulink to simulate a PLL. I have dowmloaded an M file from the ftp site "ftp.mathworks.com/pub/contrib/simulink/vco/pll.m" which in fact is a model of a PLL.
In this M file there is a VCO block, which I have also loaded. Inside the block, there is another block called "memory". I am trying to figure out the function of the "memory" block. The only explanation that I can find in the help files states : Applies a one integration step delay. The output is the previous input value. Use it to break algebraic loops."
I know what an integrator is and how it is used in the continuous domain. I know what a unit delay is and how it is used in the discrete domain. But I do not know how an integration step delay is used in the continuous domain. How do you know how long an integration step delay is ?
Please point me to any application notes concerning this topic that I may have missed.
Also, under what circumstances would I want to use the "clock" block. I noticed that it was also used in the pll.m simulink file mentioned above.
Thank you
Tom



