If there’s one thing that will bring down the yield of your PCB assembly, it’s your solder paste. Put too much on, and you’ll get bridged leads. If you don’t put enough on, that pad might not make good contact. [ScalarElectric] has an amazing trick that’s sure to astonish and astound. Just use wedges and you’ll get better yield with fine-pitched components.
The trick here is to define the cream/solder paste layer of each package as a wedge on each pad instead of the usual rectangle. This gives a few benefits, the largest being the increased gap between paste shapes. You’re also getting a reduction in the total amount of paste applied, and a subsequent improvement in yield. (Reportedly, we’d love to see some data on this.)
- When: Thursday, October 25th, 3:30 – 6:30 PM
- Where: 20100 E. 32nd Parkway, Suite 225, Aurora, CO 80016
Join us for pizza, beer and tours of our newly remodeled, high-tech facility as we celebrate 14 years in business. Bring your co-workers too!
Pamela spoke about her desktop loom project:
Designing pcbs for assembly is easy, right? We just squirt all the footprints onto a board layout, connect all the traces, send out the gerbers and position files, and we’re done–right? Whoa, hold the phone, there, young rogue! Just like we can hack together some working source code with variables named after our best friends, we can also…
[Elliot] wrote in with his OpenFixture model for OpenSCAD. It’s awesome because it takes a small problem, that nonetheless could consume an entire day, and solves it neatly. And that problem is making jigs to test assembled electrical products: a PCB test fixture.
In the PCB design software, you simply note down the locations of the test points and feed these into the OpenSCAD model. [Elliot] shows you exactly how to do it using KiCAD. There are a few more parameters of the model that you can tweak to match your particulars, but you should have a DXF outline for a test jig in short order. Cut that out, assemble, and test.