Collaborate Disseminate
Folks from [Adafruit] are showing off a neat hack – USB host on RP2040, using the now-famous PIO peripheral. [Adafruit] builds a lot of RP2040 boards, and naturally, you gotta …read more Continue reading USB Host On RP2040 – With PIO
It’s not unheard of for those who tinker in the land of electronics to suddenly find themselves with a project on their hands and potential customers clamoring at the door. Of course, the road to shipping a product is a long one, and requires a unique set of skills quite …read more
Continue reading A Budget Testing Rig For Low-Volume Production
Test and programming fixtures are great time-savers for anyone who needs to deal with more than a handful of PCBs. Instead of plugging in connectors (or awkwardly holding probe tips or wires) to program some firmware or run tests, one simply pops a PCB into a custom fixture with one …read more
Testing is a key part of any product development cycle. Done right, it turns up unknown bugs and problems, and allows for them to be fixed prior to shipment. However, it can be a costly and time-consuming process. The [Bay Libre] team needed to do some work on power management, …read more
Continue reading Process Characterization On The Cheap With A Custom Test Rig
When it comes to production, fast is good! But right the first time is better. Anything that helps prevent rework down the line is worth investing in. Some of the best tools to catch problems are good test fixtures. The folks at Tertill (a solar-powered robot for killing weeds that kickstarted last year) took the time to share two brief videos of DIY test fixtures they use to test components before assembly.
The videos are short, but they demonstrate all the things that make a good test: on the motor tester there are no connectors or wires to fiddle with, …read more
Continue reading A Peek Into a Weed-Eating Robot’s Test Fixtures
[Elliot] (no relation, but hey, cool name!) 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 …read more
Continue reading OpenFixture Takes the Pain Out of Pogo Pins
In our final installment of Tools of the Trade (with respect to circuit board assembly), we’ll look at how the circuit board is tested and programmed. At this point in the process, the board has been fully assembled with both through hole and surface mount components, and it needs to be verified before shipping or putting it inside an enclosure. We may have already handled some of the verification step in an earlier episode on inspection of the board, but this step is testing the final PCB. Depending on scale, budget, and complexity, there are all kinds of ways to …read more
In the last episode, we put our circuit boards through the reflow process. Unfortunately, it’s not 100% accurate, and there are often problems that can occur that need to be detected and fixed. That’s what the inspection step is for. One could insert an inspection step after paste, after placement, and after reflow, but the first two are icing on the cake — the phase where most mistakes can be caught is after reflow.
There are a number of problems typical with a surface mount reflow process:
Like the fictitious invention of the Hula Hoop in Hudsucker Proxy, [David Spinden]’s big idea is small and obvious once you’ve seen it. And we’re not saying that’s a bad thing at all. What he’s done is to make a new kind of prototyping connector; one that hooks into a through-plated hole like a pogo pin, but in the horizontal direction.
This means that your test-points can do double duty as header connectors, when you need to make something more permanent, or vice-versa. That’s a lot of flexibility for a little wire, and it takes one more (mildly annoying) …read more
