rjainv said:
What is the relationship between waveform of CLK1 and Clk2 ?
Are they coming from same source ? is one a divided version of other ? What is the least separation that can be between edges of CLK1 and CLK2 ? is that deterministic ?
Hi rjainv,
Thank you for your reply.
Can you please explain me for the both the case that you have mentioned ?
What if both the clks are the from the same clk source ( i think same pll )and what if the dont know the exact separtion between both the clks.
I think in practice you can not say that how much skew on clk1 and how much skew on clk2. And aprt from this we have clk uncertainy due to OCV(i.e. jitter + varialbe skew due to ocv).
Anyway,
Do you mean that if both ckls are from the same clk source than we should declare it as a multicycle path as we are knowing the phase relationship betweeen two clks, and hence no chance of timing violation and hecne no need to give false path ?
And even if the clks are not from the same clk, but if we know the phase realtion ship between the launch edge and capture edge, we can make sure that there will not any violation detected and hence no need to declare falsepath, and can give multicycle path.
If it is so, then I have one more question that, how to find out that our clks will be having such kind of relationship in terms of their phase? Even if the clks are coming from the same pll, how can we make sure that the all the clks will start from zero at the same time?
Please give me detailed answer. It will help me a lot to enhance my fundamentals...