| ??? 03/24/07 01:55 Read: times |
#135731 - an approximation is OK. Responding to: ???'s previous message |
Joseph Hebert said:
P.S. Just so you know, I'm not trying to be coy by giving you sparse answers. It's just that that this is a very complex subject and there is no simple answer to your question. I can understand, and I don't need precise values. Joseph Hebert said:
There are simple approximations that you can use to get close, but even that will require that you study the subject in significantly greater depth than you're currently exhibiting. Don't just look for a couple of "plug & play" equations. You will not be well served for having done so. Look up some literature on the subject and read. Then try to apply what you read to your problem. In the end you'll still need to do some approximating on your calculations, but you'll at least be doing so knowingly. I am making my own 8051 SBC on a double sided board for the very first time, and I think that very short tracks are great, but they might create a need for vias which I do not like to have alot of. Also, I find (from my last board) that large narrow tracks don't work as well. Because another design of mine having short enough tracks worked well, I think having really short and fat tracks are the best way to go. The design that worked didn't have all the features that I now want. My design now also involves a 74HC08 logic AND gate. I still need to figure out where to place this on the PCB. This AND gate ties RD and PSEN together so that I can use movx or movc to read code memory. I'm basically asking What are my limits with the tracks? I don't need precise values, just approximations, so that when I design my PCB, It will work. |
| Topic | Author | Date |
| Track lengths and widths (8051) | 01/01/70 00:00 | |
| Controlled impedance | 01/01/70 00:00 | |
| It wont work out | 01/01/70 00:00 | |
| See the edited version of my original reply. | 01/01/70 00:00 | |
| an approximation is OK. | 01/01/70 00:00 | |
| Hard to really guide but... | 01/01/70 00:00 | |
| thanks for the width | 01/01/70 00:00 | |
| This is why Erik goes ballistic | 01/01/70 00:00 | |
| Clock signals | 01/01/70 00:00 | |
| thank you | 01/01/70 00:00 | |
| fast signals don't care about width | 01/01/70 00:00 | |
| "Clock signals"? | 01/01/70 00:00 | |
| clock | 01/01/70 00:00 | |
| be careful, Mike | 01/01/70 00:00 | |
| 1983 Fourth Edition | 01/01/70 00:00 | |
| Length is more important than width | 01/01/70 00:00 | |
| Try this, Mike | 01/01/70 00:00 | |
| I've tried to explain this. | 01/01/70 00:00 | |
| What Mike wants | 01/01/70 00:00 | |
| I meant "Dave and Kai" | 01/01/70 00:00 | |
| I understand... | 01/01/70 00:00 | |
| Join the club! | 01/01/70 00:00 | |
| Interesting note, Kai... | 01/01/70 00:00 | |
| signal integrity | 01/01/70 00:00 | |
Very cute | 01/01/70 00:00 |