PCB layout - JHarvey

[AbeFM]

Wow, have you tried the web based autorouter? It's not fast, ok - but it's good. I had a board which coulnd't be fully autorouted in kicad... It left like five or 6 traces, which I did manually, with perhaps 5 vias each? maybe three on some, as many as 8 on others.

This autorouter already has the board down to 6 (edit 4 and counting down) vias FOR THE WHOLE THING, and I'd smooshed everything way closer. This is full auto without any help from me.

It's very nice, and integrated with kicad to some extent.

[AbeFM]

One more thing I need, then aside from the fact I utterly disregaurded keeping sensitive signals cleanly routed and using bigger traces for high current devices....

I was wondering, does someone know how to make an array of solder pads? I want to put a proto area on board, don't know if there's an easy way.

Thanks.

[Fred]

Wow, have you tried the web based autorouter?

Link ?

[jharvey]

I've tried to use auto routers for about half an hour, back in 2002, I decided yuck. I haven't tried them since.

About updating KICAD, I'd say yes I'm willing to update, however, I've never had good luck with a compiled versions of things. On several attempts I've found the compiled versions simply weren't as stable as the packaged versions. Do you know a FC8 install package? I can't update to FC9, as this boxes primary purpose is as my DVR, and the DVR soft hasn't been updated yet.

I'd say make a footprint for the proto area pads, I've not seen one yet, and if there is one, I doubt it matches exactly what we are looking for. Once you've added like 3 or 4 pads, open the file with a text editor, and copy paste the text, then modify the numbers to change the pad spacing spacing. If you want to get real fancy, make the pin tables in a spread sheet, use an equation to generate the text, then save the values to a text file.

[Fred]

Don't be afraid of the source, Luke!

FreeEMS builds will be built from source (or course) and in fact, I built my GCC from source too ;-)

If it states that the one we have is current, you should find an rpm of it.

Fred.

[jharvey]

About the star wars reference, seems like there should be a cleaver reply, however, it's not comming to me. So instead go here.

http://www.asciimation.co.nz/

Note the .nz thing.

Also I sort of lied, I've had some success on installing some programs from source. However they were very similar to FreeEMS and specically design without platform specific dependencies. FLDigi worked well because he wrote almost all of it himself. I seem to recall he only relied on two outside program dependancies, that were very stable. A common problem I've had is that the the software was developed with program A at version blah, and program B at blah, ect. Then when someone else compiles, but they are set with program A at version bla, and program B at version blahh, it flopps until you get the dependecies to match exactly what it was developed against. I also remember failing because the OS had changed some thing about unicode. I still don't understand that one. Had to do an override when I called make, ect. Even then it didn't work stable when it finally did go. Most of these problem are fairly small to many programmers that keep them self up to snuff on the changes happening to the OS they are working with. However, I can't do that. I'm more of an end user than a programmer when it comes to that kind of stuff.

Some issues I potentailly see from KICAD include dependencies, file locations and file permissions. I doubt it would go smoothly. I'll have to see if I can find a repository somewhere with the latest for FC8. If I find something, I'll be sure to post about it.

[AbeFM]

I've tried to use auto routers for about half an hour, back in 2002, I decided yuck. I haven't tried them since.

I would give it a shot - the best part about this is it's easy to move stuff around afterwards - drag components, move traces, etc etc. It's easy to do, click the top right button in the layout program

I'd say make a footprint for the proto area pads, I've not seen one yet, and if there is one, I doubt it matches exactly what we are looking for. Once you've added like 3 or 4 pads, open the file with a text editor, and copy paste the text, then modify the numbers to change the pad spacing spacing. If you want to get real fancy, make the pin tables in a spread sheet, use an equation to generate the text, then save the values to a text file.

Not a bad idea - I could try that! Even a little tile I could stamp many instances of them down.

[AbeFM]

I may figure this out with more digging, but.. How do I put in wider traces? I seem to be able to go narrower, but 17 mil is all I get? I'm thinking injectors will want at least 2 Amp steady... Unless I get a thick pour, that's barely usable on a 17 mil trace. Factor in that at high load, 85% DC, and higher peak currents in the ballpark of 7 amps... And I'm really going to want to have 25 mil or bigger traces.

[Fred]

thou, mil implies mm :-p get with the game.

25thou is urrr 0.63mm

surely you want more than that?

injectors go down to 1ohm and at 15V thats 15 amps!

I'd've thought more like 1.5 - 2mm ? or am I being ridiculous ?

[jbelanger]

thou, mil implies mm :-p get with the game.

Sorry to disagree with you but mil is the unit used on board layouts (even in European software) and it means thousandth of an inch. If you want mm you use mm.

25thou is urrr 0.63mm

surely you want more than that?

injectors go down to 1ohm and at 15V thats 15 amps!

I'd've thought more like 1.5 - 2mm ? or am I being ridiculous ?

Even with a 1 Ohm injector, I doubt you'd want to let the current go to the maximum possible so it would have to be limited somehow. The most current I've seen for peak & hold injectors was 8A. But I agree that if you want to handle that (and survive the accidental 15A) you definitely want to go more than 25 mil. Using a minimum of 50 mil would be ok with "standard" p&h injectors and 75mil would not be over the board. If you plan on having on-board ignition IGBTs then 100 mil would make sense. (50 mil = 1.27mm, 75 mil = 1.9mm, 100 mil = 2.54mm).

Jean