Minimum via size for seeed/itead

[8086]

I wonder if anyone has tried really small vias with success from seeedstudio or iteadstudio?

They specify 0.8mm finish hole, 0.3mm drill hole, but 0.8mm is pretty large for my current space-limited project.

Anyone tried under 0.8mm with success? Ta.

[papo]

Hello

Anyone tried under 0.8mm with success? Ta.

Yes. I was wondering about the same a while ago and checked their eagle design rule file. I don't remember what was in there, but it was smaller than the drill size quoted in their table. I'm not sure whether I got lucky or not, but I used these figures, they didn't complain and the boards were flawless.

Regards
Matt

Edit: This was seeeed.

[8086]

Thanks, I just downloaded the eagle design rules and had a look.

Seems like you can go down to 12mil hole (0.31mm) and 24mil overall diameter (0.61mm). Better than 0.8mm hole thats for sure!

[Dago]

I have always used 0.3/0.6mm vias with itead and seed without problems.

[8086]

So I have ordered some boards with lots of 0.62mm diameter vias with 0.32mm hole size from seeed. When they arrive I'll see if they actually work.

[8086]

So I have ordered some boards with lots of 0.62mm diameter vias with 0.32mm hole size from seeed. When they arrive I'll see if they actually work.

I received my boards today, seems to be a success! 

[peter.mitchell]

hey 8086, would you be able to take a close-up of around the outlined area;


i want to see how good the soldermask between pads and the vias in pad are, if you feel uncomfortable posting in the forum, that's understandable.

[8086]

This is about as up close as I can get - haven't had a good camera for a while.

[peter.mitchell]

This is about as up close as I can get - haven't had a good camera for a while.

Thanks! What mask expansion did you use? On some pads/traces it looks quite large.

Also, you're the fellow that does assembly in the UK correct? Just wondering what flux cleaner you use? I've been using MG Chemicals "Flux remover for PC Boards - 4140" and getting a fair amount of residue (even though quoted as zero residue) and require a quick wash of isopropyl to clean that.

[poorchava]

My standard via size is 0.35mm/0.7mm hole/via diameter. I'm usually ordering from Elecrow and have used iTead before, but I guess they use same fab houses as seeed and others. I've never had a failed via and never got a DRC question from Elecrow or iTead.

I recall using 0.3/0.65 somewhere, but I don't remember whether they sent to production that way.

[8086]

Thanks! What mask expansion did you use? On some pads/traces it looks quite large.

Also, you're the fellow that does assembly in the UK correct? Just wondering what flux cleaner you use? I've been using MG Chemicals "Flux remover for PC Boards - 4140" and getting a fair amount of residue (even though quoted as zero residue) and require a quick wash of isopropyl to clean that.

I intended 0.102mm soldermask expansion. The width of the QFN pads is 0.25mm so it looks like it's close but maybe not quite right. Still, close enough for me.

I am that fellow, indeed. I have been getting good results with the PCB cleaner aerosol sold by Maplin. I usually clean with IPA first of all, with the help of a small brush, then give them a spray with the aerosol and it leaves no residue.

[Milentije]

I received my boards today, seems to be a success! 

What? You ordered these PCBs from itead/seed and they routed it like this (non-rectangular shape)? Was that some special order or the regular one?

[8086]

What? You ordered these PCBs from itead/seed and they routed it like this (non-rectangular shape)? Was that some special order or the regular one?

I ordered from seeed, and yes they have no problem with unusual shapes, as long as there's no internal cut-outs. I've ordered several non-rectangular boards and they've never had a problem with it.

[Milentije]

Oh, my bad. I thought you panelized this design.

[free_electron]

12/24 with 8/8 or 6/8 clearance

12 mil hole
24 mil pad
6 mil track 8 mil gap (they prefer 8/8/ but have no problem with 6/8