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Comment by LoganDark | Hacker News Reader

I've been trying to make a PCB but it's just so annoying having to sift through pages and pages of listings in order to find each individual tiny component without minimum order quantities of hundreds or more. The process of finding each component is so tedious that I gave up. (I was using EasyEDA hoping it would be easy to find components I could actually order -- nope)

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Part selection is often the bulk of the work in a PCB design, yeah. What tools were you using, though? In general the parametric searches on digikey, mouser, etc are pretty good for the standard components. For stuff like resistors it's generally easiest to find a particular range and pick from those. You might find most of those have a MOQ but they're cheap enough it's usually not a major issue.

What kind of part? I use Octopart for a lot of things, like ICs (sometimes some variants are available in low quantities but others aren't and only in thousands).

For stuff like passives it's usually easier to use Digi-Key or Mouser and you can filter by MOQ so you only see things that are available individually.

the most annoying was stuff like resistors or capacitors. They tended to have huge minimum order quantities, there were hundreds of results for any kind of query and most of them were always out of stock. I wanted to stick to JLCPCB's platform so that I could order the boards pre-populated, but I didn't want to be stuck ordering far more components than the board actually needs.

I always feel anger or something when I see some YouTuber say they easily made a board and ordered it pre-assembled from JLCPCB. They make it sound like it's so painless, but for me it's mostly searching through part listings trying to find one without a minimum order quantity of like 100, because there are no filters or sorts for that

Were the MOQ for the resistors a major contributer to cost? Usually they're super cheap so even buying 100 is not a crazy problem. Also most PCB assemblers will have a generic component library for common resistor and capacitor values and footprints, which they encourage you to use anyhow because it's less hassle for them (they're often not even charged per part).

(And if you're assembling them yourself, then you can also buy kits of the common ranges to save the hassle and cost of having to maintain a stock)

If you have dozens of different passives on the board, then a dollar or two to meet each minimum order quantity adds up quick.

DigiKey used to be a good place to get. Also design for parts you can get... In the old days you could also get samples from chip companies if you asked nicely. No idea if anyone still does that.

Some still do, but they'll only send to businesses, not to individuals.

What's annoying for me is Digikey and friends insisting on only delivering with express carrier. I'd like to have a cheaper, slower option.

So a lot of this goes away if you try to stick to jlcpcb basic parts from lcsc, and you sort of develop preferred components for things. Another trick is when in a category, for example angular hall sensors, once you have the key attributes like vin, smt, etc, sort by quantity desc to see what parts get heavily stocked, that tends to indicate what is popular in industry and likely to be a good generic fit. Out of the top 10-20 pick according to stock level against price. If youre ordering from jlc, look through lcsc and you can do pcba with them, or get the parts shipped with the pcbs. Otherwise digikey, mouser (good for connectors), farnell, rs etc, roughly in that order. You will quickly learn for a lot of components there are very standard parts everyone uses. Diodes, inductors for example. To some extent if your footprint is already in the jlcpcb library, its popular and use that. Ie theres 1 smd push button that is basic on jlc and has a footprint in kicad default library. Youd be a little crazy to use anything else. Make all your resistors and caps 0603 or 0402, jlc stocks those the most, vs spotty coverage in 0805 or 1206.

But you find each time you find something in a category, a hall sensors, an encoder, a capacitance sensor, gpio expander, adc, you just file that away as kind of solved and next time you hit that part first before finding alts. Over time you have to dig about less and less. But dont bother with things like resistors, caps, etc that are basic. Even mosfets, unless you have special needs the 3 main types jlc has as basic are fine. Dont get some odd package thats technically two mosfets in one, just put down two basic mosfets. And if you do need a more 'advanced' part, look what is on jlc's promo list atm. Theres very popular stm's for example that are prettymuch constantly on promo (promo is they have the part loaded in mid term for some big customer so you might as well piggyback. Means no loading fee. Adds up)

Llm's can be useful for sifting the sand. Narrowed it to like 30 options and still dont know whats the best pick? Export search as csv and ask your favourite stochastic parrot which part would work best for your application and why. Dont ask them for part numbers though, completely pointless.

LCSC has been my problem. It's built into EasyEDA, but most search results aren't in stock, and most of the rest have high minimum order quantities.

I needed a lot of different resistor, capacitor, etc values so each and every one needed me to go through that search.

Yes, you need to design for what jlc stocks as basic parts to retain your sanity. Dont just slap down a 1206 resistor and call it good, jlc prob has no stock in that size in that value, but they probably have it in 0603. Once you get a handle for whats basic or very common extended parts, that sort of thing gets a lot easier. You kind of have to work backwards, ie if i need a diode i see what jlc has in basic and make my part choice accordingly.

I wasn't trying to choose a footprint/etc ahead of time. I would need, say, a 3.3KΩ resistor, and I would not filter for anything else other than the resistance yet, then I would choose a listing that I could use and that had a reasonable footprint and etc.

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