jitter and noise performance of 74xx AC and VHC series?

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Hi,

What is the main difference between the 74xx AC and VHC series, especially in terms of jitter and noise performance?

I went through some of the datasheets (74AC161/74VHC161, Fairchild), I am unable to find any relevent info, can someone help?

Which series, VHC or AC, has better jitter and noise performance?

Thanks

PW:bigeyes:
 
inverter Toshiba 74HCU04

I had very good sonic result using better filter (L 10uh) and decoupling (lots of smd 805 cg0 and x7r) of this chip for clock in pd75/65 player. Only a few tweaks have been sonic better; as lowering pll.

I am no expert but as I understand it this inverter has low psrr, and is often used without enough "speed" in decoupling (also groundbounce) -> jitter.

Se this - it is in danish - but go to:
"Optimering nr. 4. – Jitter optimering"

http://www.hifi4all.dk/forum/forum_posts.asp?TID=6730&KW=optimer

As a general rule, use only the nessesary speed. A rise time of 4ns is only nessesary if signal travels for longer distance.
 
In general, 74AC devices produce more supply-rail noise than VHC ones, so this may translate into jitter problems. (Although having said that, modern 74AC parts seem to be a lot quieter than the earlier ones).

If you are using 3.3V rails, then 74LVC or 74LCX parts work very well.
 
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