Minimum via size for seeed/itead - Page 1
Forum section: electronics / general

author: 8086
author_rank: Super Contributor
timestamp: March 02, 2014, 03:48:12 pm
content: 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.

author: papo
author_rank: Regular Contributor
timestamp: March 02, 2014, 07:51:35 pm
content: HelloQuote from: 8086 on March 02, 2014, 03:48:12 pmYes. 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.RegardsMattEdit: This was seeeed.

author: 8086
author_rank: Super Contributor
timestamp: March 02, 2014, 08:11:33 pm
content: 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!

author: Dago
author_rank: Frequent Contributor
timestamp: March 03, 2014, 11:59:49 am
content: I have always used 0.3/0.6mm vias with itead and seed without problems.

author: 8086
author_rank: Super Contributor
timestamp: March 12, 2014, 08:20:31 pm
content: 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.

author: 8086
author_rank: Super Contributor
timestamp: March 25, 2014, 11:13:50 pm
content: Quote from: 8086 on March 12, 2014, 08:20:31 pmI received my boards today, seems to be a success!

author: peter.mitchell
author_rank: Super Contributor
timestamp: March 26, 2014, 06:03:13 am
content: 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.

author: 8086
author_rank: Super Contributor
timestamp: March 26, 2014, 01:57:17 pm
content: This is about as up close as I can get - haven't had a good camera for a while.

author: peter.mitchell
author_rank: Super Contributor
timestamp: March 27, 2014, 01:07:30 am
content: Quote from: 8086 on March 26, 2014, 01:57:17 pmThanks! 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.

author: poorchava
author_rank: Super Contributor
timestamp: March 27, 2014, 11:59:35 am
content: 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.

author: 8086
author_rank: Super Contributor
timestamp: March 27, 2014, 01:47:40 pm
content: Quote from: peter.mitchell on March 27, 2014, 01:07:30 amI 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.

author: Milentije
author_rank: Contributor
timestamp: April 13, 2014, 06:02:49 pm
content: Quote from: 8086 on March 25, 2014, 11:13:50 pmWhat? 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?

author: 8086
author_rank: Super Contributor
timestamp: April 13, 2014, 06:08:24 pm
content: Quote from: Milentije on April 13, 2014, 06:02:49 pmI 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.

author: Milentije
author_rank: Contributor
timestamp: April 13, 2014, 06:37:47 pm
content: Oh, my bad. I thought you panelized this design.

author: free_electron
author_rank: Super Contributor
timestamp: April 13, 2014, 06:42:00 pm
content: 12/24 with 8/8 or 6/8 clearance12 mil hole24 mil pad6 mil track 8 mil gap (they prefer 8/8/ but have no problem with 6/8