In SX Microcontrollers, SX/B Compiler and SX-Key Tool, dkemppai wrote:

[2]
Peter,

First off, I have to deal with Non Disclosure Agreements. I can't post details. People could loose their jobs, Period. 

Now, you are correct, if you looked at the title of the post, a good portion of the posts were off topic. "Resonator Tolerances. Higher Tolerance Pairs or matching?", was a question of higher tolerance resonators. Even so, I tried to respond to everyone's suggestions, because I DO appreciated the input, and time spent making the suggestions.

If you look a the initial tolerance of the Resonators plus minus 0.5% (+-5000 ppm). That means that there is potentially 10,000 ppm mismatch in clock frequency between any two resonators. This does not include temperature effects potentially pushing that mismatch to a maximum of 15,000 ppm. Then add to that aging, and jitter introduced through the transmission media, things start to stack up. The bottom line is resonators are REALLY POOR FREQUENCY SOURCES. I really would like to use a single digit ppm tolerance device, but trust me, they won't hold up. 

Also, Please don't assume you could do my job any better than I can. I've been engineering solutions for complex problems for a long time, and I'm pretty sure I know a bit more about my engineering problems than you do. 

I'm here because it never hurts bounce ideas off of others. And, that's just what I did.  

-Dan
[/2]

---------- End of Message ----------


You can view the post on-line at:
http://forums.parallax.com/forums/default.aspx?f=7&p=1&m=88814#m89376

Need assistance? Send an email to the Forum Administrator at forumadmin@parallax.com

The Parallax Forums are powered by dotNetBB Forums, copyright 2002-2005 (http://www.dotNetBB.com)