Go Down

Topic: can you take a look at my eagle pcb design? (Read 2268 times) previous topic - next topic

lax123

#15
Feb 25, 2013, 08:54 pm Last Edit: Feb 25, 2013, 08:56 pm by lax123 Reason: 1
So I just could ignore those errors as its not actually a part but several vias combined?


Well actually I used "real" connectors at first but they didnt work as they are like 2 mm too large and wont fit on the 5x5cm (see attachment)
Otherwise I would not have gone through the trouble of creating a new part for the library, creating footp and symbol and pinconnections. But maybe there is a more clever way I dont know of.

vasquo

You can change your pads from oval to a round, or square.
If you have the actual part you'll be using, measure it with a digital caliper and see if it will really fit or not. Sometimes, the part outlines in these libraries are not accurate (too small or too large).

Now, whether you can ignore these DRC issues or not, well... it's up to you.
This is just a computer screen.
You can make it "work" on your computer screen, but who knows... you may be surprised when you get your boards back from the PCB fab house and it's not what you expected.
or it "works" on your computer screen but the PCB fab house wouldn't manufacture it because it didn't conform to their DRC.

There are certain DRC warnings I ignore, but only because I know my PCB fab house and know they can manufacture it without problems.

Chagrin

Seeed will allow the pads that close to the edge. The extreme would be castellated pads and that is possible with their service.

Not really a good practice though. You've got lots of board space and you should use it rather than creating physically weak areas on the edge of your board.

lax123

Quote
You've got lots of board space and you should use it rather than creating physically weak areas on the edge of your board


how can i achieve that? mega is 5,5cm wide and seeed max 5 cm (unless i want to pay extra 15$ for 5mm), so these connectors have to be that close to the edge otherwise it wont fit on the mega

Chagrin

Whoops I was totally oblivious to the fact that this is a shield.

Here's an example of a Seeed user that created a shield using their service and squeezed their pin holes right on the edge like you're doing. Worked for him so you should be OK.

http://www.seeedstudio.com/forum/viewtopic.php?f=9&t=2416


lax123

measuring the distances of that above shield -its wrong in top header length, its 39,69 while from mega reference design i get 39,37. And bot headers are not perfectly aligned with top headers as in reference design where the middle of bot a hole is in exact middle between two holes at top.

Seems that those differences of 0,32 mm do not matter, is that true, or did that guy have a hard time fitting the shield on the arduino and didnt tell, or are my measurements wrong?

lax123

#22
Feb 27, 2013, 12:21 pm Last Edit: Feb 27, 2013, 12:26 pm by lax123 Reason: 1
also i wonder if this way of trying to attach the dc jack regarding the drillholes is better in contrast to the one in my first post. Has somebody experiences with those?

vasquo

Fab house usually reject overlapping drill holes. It breaks their bits. 

The first library will work. The "spade" of the DC jack fits in the diameter of the hole.

lax123

well, i read seeed has no problem with that. if its no problem, which way is better of doing it?

As i have not done that before: is it not problematic that there might be a lot of space left when i choose those big holes? its not a round big pin but a rectangular one on the dc jack.

CrossRoads

Go surface mount on the DC jack, makes the hole problem go away.
http://www.digikey.com/product-detail/en/PJ-002AH-SMT-TR/CP-002AHPJTR-ND/408452
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

lax123

i already bought it and have it right next to me :/

CrossRoads

Then solder it into a standard set of holes - what's the big deal?
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

lax123

Hi,

standardhole: its just that i dont know if it can be problematic if the pin i want to put in has the width of that hole but is much much smaller in length.
but i guess ur answer -whats the big deal means its not a problem at all. thanks

Go Up