PCB making advice please

Has anyone made a home PCB using a 14 x 14 mm 100 pin QFP, I’ve just spent 4 days laying it all out, I’ve now printed it out to look at and I’m beginning to doubt that I can etch it. Basically I am looking for someone to tell me it’s possible to give me a bit of confidence.

I think its possible (although I have no direct experience) with the QFP
100 because it is still a 0.5mm pitch unlike the 128TQFP types where it
moves down to a 0.4mm pitch, those are really tricky and having a fine stop
mask in between makes the soldering much easier than on a non masked DIY


Thank you very much Alan.

To be quite honest, I have since discovered that I had made a mistake, I created the library QFP 100 with the pads just very slightly too wide, I have previously etched 0.5 centers for a camera connector and now I have corrected my foolish mistake, it may be possible.

Sometimes in these situations, you just need to talk to someone.

For pics and progress, see here:
[Wifi Cam - Stage 1][1]
[1]: http://trevmhomers.blogspot.co.uk/2015/02/23022015-wifi-cam-stage-1-moved-into.html

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I just did my first 0.5mm board yesterday and I’d say “yes, it’s possible”. Unfortunately mine didn’t turn out perfect - I changed some of my process around a bit and it was a little underexposed. I also has the ground pour isolation a little too tight at 0.005".

The components are 48LQFP, 32QFN and 0805 passives. It might be salvageable.

Mine was a total s***w up :frowning:

It is possibly over stretching my skills, I want an ST ARM processor (100 pin 0.05 mm pitch LQFP) attached to: 2MP camera (25 pin 0.05 mm pitch), SD Card, ST-Link interface, Serial interface, Wifi (ESP8266) interface. All 0805 caps and resistors except the SMD electrolytics. I thought I could get away with solder vias under the MCU, which I discovered was really wrong.
That layout took me a week, now starting from scratch.

I’m using Eagle PCB layout package, what are you using?

I’m also using Eagle, and I’ve had plenty of screw ups myself. Everything from swapping VCC and VSS, to etching off all the copper when overexposed. Just learn as you go. I’m certainly no expert.

I normally try to at least have traces between sections that I can cut if I’ve messed up. That way I can at least test, learn from, or use part of the board. Not easy on something as complicated as you’ve described though.