Amateur electronics in danger due to lack of DIP ICs

I buy little surface-mount adapters. We don't stock any DIP packaged ICs any more.

The soldering trick is to go ahead and glob all the pins with solder, short them together. Then use solder wick to slurp off the excess.

You can also lay out a 2 or 4-layer PCB and have a cheap quick-turn house make a few. That's better than hand wiring for complex stuff.

Hey, I was scared of 1206 parts once. Now they look gigantic.

Ever hear of a reflow oven? Whole boards spend minutes above solder melting temperature. Works fine.

tirsdag den 23. februar 2021 kl. 01.47.24 UTC+1 skrev John Larkin:

some even use wavesoldering, so smd and through hole can be done at the same tie

tirsdag den 23. februar 2021 kl. 00.47.48 UTC+1 skrev Cursitor Doom:

well, if you only use 30 year old parts ...

I had a pretty rough last year but I'm back on my feet now and ready to get to work again designing electronics.

Thanks for the welcome back. John

My box builder has a row of at least 20 residential dishwashers. All boards come off the line and into those dishwashers. Even water-soluble flux boards. That is the way to clean boards. I know they use a detergent but I don't know which.

John

I was concerned before I first did SMD assembly. It was easy, and now I prefer it.

The OP shouldn't listen to reactionary old farts that refuse to keep learning and experimenting.

Just so :)

But I hate 0402s and smaller. They are difficult to manage by hand and tombstone in production. Since we use reference designators and need vias and traces too, there's not much advantage going below 0603.

Realized that should be "tack one corner down"

They're a win with microwave parts, though, and N in parallel between topside pours (with mega via-stitching on the ground pour) makes a nice low-inductance bypass.

Cheers

Phil Hobbs

We use the sideways caps for fast stuff, like 0306s. They are short in the dimension that matters.

For AC coupling, calculate the trace width and pick a cap just about that wide to bridge the gap.

neonjohn wrote in news: snipped-for-privacy@4ax.com:

John Larkin wrote in news: snipped-for-privacy@4ax.com:

With the density level of your instrumentation circuits, you could (should) hand assemble the first articles anyway. Maybe even the entire production, short of bga devices and even those can be hot air mounted. And you would only need reference designators on those parts which are integral to fault determination on a 'broken board'. A good technician shouldn't need a road sign on every corner to trace out a circuit during a diagnostic as long as a few key elements get tagged. And a grid reference 'sheet' would be easy as well.

With HV designs, we didn't go much below 0805 and HV sections had slots between pads. Anything smaller would likely not be very durable. I hand soldered hundreds of tiny HV power supplies that a couple years of development and customer decision based mid design alterations, ultimately pumped a single 15kV output with medical grade human contact circuit interruption current shutdown trigger well below the spec on current and clamp time. I think it was like

snipped-for-privacy@decadence.org wrote in news:s13h3f$1o0e$1 @gioia.aioe.org: snip

Forgot to mention that reduced pressure is always nice (read contributory to the evaporation and evacuation of water throughout the assembly.

Fine pitch, LGA, and BGA are normal. Those don't work by hand.

Maybe even the

Hand assemble without reference designators?

Hot air doesn't control temperature profiles, or prevent oxidation. We have a reflow oven with nitrogen. That's the way stuff is built now.

How do I get ref desigs on SOME of the boards? Add as needed?

Manufacturing, test, and engineering all want reference designators. I want ref desigs. 50 mils high is about as small as works for everyone.

Better you than me.

We have a giant water-wash machine, built around a modified Kenmore dishwasher.

John Larkin wrote in news: snipped-for-privacy@4ax.com:

Comes from also being the one that did the layout, and from circuit familiarity.

John Larkin wrote in news: snipped-for-privacy@4ax.com:

Like I said, I don't think your circuits are all that dense.

Wouldn't be hard with the engineering printouts of the schematics and trace layouts. Sheesh.

The silk screen and the ref des in the schematic are two different things. You do not have to print them all. In HV sections you can't if you know what you are doing. The multiplier section doesn't even get a mask layer.