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Questions relating to designing PCBs
By WBrumble
#178979
All,

I gave up on Altium, way to steep of a learning curve for me, picked up Eagle Cad and in less than an hour I found a great tutorial and learned how to make a proper footprint, versus a couple days of messing with Altium and never figured it out, ha ha.

Okay, I'm making an LED array of 52 LEDs. My question is, they are in series, and what is the minimum distance between the two component pads that will have a trace running in-between the two pads?

Right now they are spaced 10mil apart according to an article I read at aa-pcbassebly.com.

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By WBrumble
#178987
Leon,

Thank you for the response.

I will be running a layer for each die around the ring to handle the current with vias to the top layer.

The track width according to circuitcalculator.com's calculator requires it to be a minimum of 0.874mil and that's at 125% of the load, that is obviously very small.
What is the standard min width that's generally accepted by board houses as manufacturable?

Also on another note I've googled if it is okay to put vias underneath a component, couldn't find a answer to the question. Only that it was bad to put a via directly on the
solder pad.

The led's I'm using are not high power leds and they do not have a thermal pad in the center and I'm wondering to save room as I'm restricted for space on this board. Can
I put a via underneath the component? I want to run a track from the solder pad to the center of the component and down a via to a power layer if I am allowed to do this.

According to an article I read it said to keep all components and traces 125mils away from the edge of the board so that the machine can grab the board. What about milling the inside? How far should I keep components and traces from a milled open area?
Thanks again for the help!
User avatar
By leon_heller
#178990
8 mil min. is most suitable for the low-cost PCB suppliers, like ITead.

It's OK to put vias under parts. Vias in pads are a bad idea because they rob solder from the connection. They can be filled, but that is expensive.

You need to ask your board supplier about clearances.
By WBrumble
#179031
Thanks for the solid advice guys.

Looks like there's a bit less than a .20mm gap underneath the middle. I've attached a screenshot not very clear but it's due to a poor quality pdf. Attached the datasheet.

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Trying to source out a small SMD 1A 12-15vi to 12vo regulator I can mount on the board? All the ones I keep pulling up require 20vi to get 12vo.

Cheers
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By InactiveUser001
#179052
If they are 10th apart then your not going to get a track between them.

On a fine pitch board with a BGA & fine traces made professionally maybe (at higher cost) but not on a board being made by a relative newcomer using Eagle.

Run your trace elsewhere.