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Hey guys...

I am looking to get pin headers SMALLER than the normal 1.0" spacing headers that are in Eagle..

I was looking around to see if I could find/use some 0.05" spaced holes/pads....

I havent been able to find anything similar...

the only thing I could think of that used them was a Femtoduino board...  but searching I dont think there are any Eagle files for it?

problem:

PCB is so tiny.. there is really NO ROOM left... so I am stuck trying to think out of the box on HOW I can add in (at least) the serial programming pads/vias to this PCB...  (adding in ICSP pads would be nice too...but I dont think possible)..


I'll post up some pics to show this 'challenge' of a PCB I am working on...

notes:
* inner circle/ring on the dimension layer is there for visuals only.. to let me know I cant place anything INSIDE that area..will be deleted before files sent out.
* top side cant have ANYTHING on it except the main 328P chip.. and the 5 leds at bottom..   (it can have holes/vias..etc..  trying to put outside the inner circle)
* as you can see it is PACKED.. and still have to squeeze in:
     * battery +/- pads
     * 1 x switch pad
     * speaker +/- pads
     * 4 x resistors
     * serial programming pads/vias for sketch uploading   (rx/tx/gnd/3.3v/dtr)


I was thinking I might be able to put some serial programming (not ICSP for bootloadier flashing) pads on the TOP of the PCB..  right outside that inner circle...

other questions:

1.) this is the first time Im attempting an 'odd' shaped PCB.. (ie: not square/rectangle)..  does it look correct?
2.) I want to have some 'holes' drilled in it... so the PCB can fit under a part..and have holes for the posts/stand-offs on the part the pcb is going into.. I wasnt sure on how to do this?  Is this done on the dimensions layer? with a line tool? or can I just have drill holes like I do now? and expect the same results?
3.) drill hole symbols themselves..I see an inner circle with an X in it.. and then the outer circle.. what part is the actual OD of the drill hole?  the outer circle/ring? or the inner with the 'x' in it?


here are some pics of the current PCB current state:

top:  (inner circle cant really have much in it... 95% of everything needs to go on bottom.)   outer circle/ring.. (top) I can put some vias for serial sketch uploading.. at least thats my train of thought currently)



bottom: where everything really needs to go.. (but is hard because the uSD socket takes up all the room!)  lol



both layers together:  (you can see most of the components have been added..(except stuff off to the right still.. "&" the serial pads)


here is a quick pick of the 'prop/part' Im trying to design the pcb for.. so you can visually put things into perspective on how its being used, and why nothing can be on top really..etc.









I'll be cutting a hole in the bottom piece to accommodate for the uSD socket depth...to allow for the top bezel piece to sit flush in the post/stand-off holes..etc.



** thoughts/proposed solutions:

1.) take out the 1 drill hole.. in the upper corner by SD card.. so I can lay down some 'pads' (not through hole) for serial programming?.. I can utilize the obttom of the board in the same area for more pads? components?

2.) to reduce the pads left that need to be placed..(on the right side of last image)..  I was thinking of take the 2 switchpads.. and 2 speaker pads.. and sharing the GND pad?


I was thinking I could just use some .05" spaced holes like the femtoduino.. but as I was typing.. I think I dont need/want via/through holes... I can just use some pads closely spaced together.. and use those to upload my sketches? (serial)


figured Id tap the brain trust here.. as Im sure MANY of you have been down the same path.. and have learned some neat tricks or populating components on small pcbs..etc..

thanks!





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I am looking to get pin headers SMALLER than the normal 1.0" spacing headers that are in Eagle..

Wow that must be a huge layout presently?  smiley-grin
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lol..

oops.. 0.1 spacing.. smiley

any pointers? suggestions?  smiley

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1.) this is the first time Im attempting an 'odd' shaped PCB.. (ie: not square/rectangle)..  does it look correct?

It looks like your mounting hole is going to rip the edges of your board. It's almost tangent to your board.

Quote
2.) I want to have some 'holes' drilled in it... so the PCB can fit under a part..and have holes for the posts/stand-offs on the part the pcb is going into.. I wasnt sure on how to do this?  Is this done on the dimensions layer? with a line tool? or can I just have drill holes like I do now? and expect the same results?
You can use mounting holes from the "holes" library in Eagle.

Quote
3.) drill hole symbols themselves..I see an inner circle with an X in it.. and then the outer circle.. what part is the actual OD of the drill hole?  the outer circle/ring? or the inner with the 'x' in it?
The cross is the drill center mark.  The inner circle is the diameter of your hole. This will be taken out during pcb manufacturing. The bigger outer circle is clearance area... (Because your mounting bolt, will have a head. The head is bigger than the diameter of the bolt.).  The next circle is tRestrict, so if you fill up your copper plane, there's clearance/margin so your metal bolt head isn't shorting with your bottom or top copper layer. 


* holes.gif (16.59 KB, 1063x687 - viewed 10 times.)
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Hey guys...

I am looking to get pin headers SMALLER than the normal 1.0" spacing headers that are in Eagle..

I was looking around to see if I could find/use some 0.05" spaced holes/pads....



Something like http://uk.farnell.com/samtec/fts-115-03-l-dv/header-1-27mm-smd-30way/dp/1667738

You can get 2mm headers too, a lot less fiddly.
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