PCB Supplier Recommendations - 4 layer

I recommend you avoid Sunstone Circuits. They really screwed up my orders the one time I used them. One was misplaced delaying it by over a week and the other produced crappy boards with a high drop out rate. The panels they sent me had a huge number of X-outs and the ones they say passed test still had 20% failures.

Interesting. How long ago was this and what were your board specs? I've always had good results from Sunstone, but I haven't ordered anything too exotic from them, just 4 and 6 layer with 6/6 trace/space.

My biggest complaint about Sunstone is their 6-mil silkscreen line width requirement. Most other PCB manufacturers seem to support much smaller text characters.

-- john, KE5FX

The one they screwed up was 6/6 trace space and 10 mil drill vias. I think they said they rounded the drill up to 13 mils since that is "within" their tolerances. I was not able to get several boards to work out of the 20 I ordered. I suspected open vias, but couldn't find them. Getting 15 working met my immediate needs so I punted the problems and found someone else. Now my contract manufacturer has the PWBs made and I won't worry with it.

Oshpark will do 4 layer, $10/sq inch for three copies. Not exactly quick turn but cheap for very small boards.

I guess the reason I am so pissed with them is that when they held my order for a week instead of expediting it, they argued with me and blamed the delay on me. Then I gave them a credit card number and they lost it... two times! During none of this did I get confirmation of anything happening. I would have to call every time I wanted insight to what was happening.

Den mandag den 28. december 2015 kl. 23.57.34 UTC+1 skrev tomcees snipped-for-privacy@yahoo.com:

-Lasse

Don't use MyroPCB. The pads fall off.

Do any of the PCB manufacturers have a layout done for the 72-Lead Lead Frame Chip Scale Package [LFCSP_VQ] (JEDEC STANDARDS MO-220-VNND-4) from ADI?

If necessary, I'll create the part myself, but it would save me a lot of time if the layout exists already.

Thank you in advance for helpful, positive advice, TomC

"Footprints" are specific to the board layout software. PCB manufacturers don't traffic in footprints (unless perhaps you've made the blunder of choosing one that only works with their own layout software).

Thanks for the reply.

I understand that the footprint is specific to the software used.

I have not yet made a choice of whose software to use and was intending basing that decision on what supplier had these footprints available.

However, if there is a more generic method of develop and using these footprints, I would be most curious to know what the recommendations are. If there is public domain or reasonably cost software, I'm open to recommendations.

Regards, TomC

For the software: KiCAD

Any PCB CAD software worth buying (or downloading) will let you define the footprints exactly the way you want them (ignoring resolution). Whether the PCB manufacturer can actually manufacture them the way you draw them can be a question- a question answered by referring to the design rules or capabilities or whatever the PCB manufacturer calls them.

For example, the minimum via size, the minimum annular ring (copper around a drilled hole) minimum solder mask sliver, minimum trace width and trace spacing etc. etc. The rules will vary from maker to maker, and within a supplier's line by number of layers, copper thickness and so on. It's unwise to use the absolute limit of what they can make anwhere where it is not needed- and you may wish to use a bit worse than the lowest common denominator of viable suppliers so you have choices when it comes time to purchase.

For footprint design, the reference is IPC-7351. Some software packages such as Altium have 'wizards' that apply the rules (and some defaults) to allow you to quickly create footprints, but you can try to create an IPC footprint with rubylith and an X-acto knife if you want to.

--sp