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metafex | 6 years ago

Because I see it again and again: Please don't put 20 years old dc/dc converters into new things. Neither price nor package are valid resons.

There's cheaper and better ones available in similar or the same packages. E.g. LCSC is a perfectly valid source for many chinese brands and cheaper ICs, so availability is also not a reason.

Now for the last: familiarity. If you have to take a ti simpleswitcher because you're scared of DC/DC's, that's also perfectly valid, but again, there are newer ones which are better all around.

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LeifCarrotson|6 years ago

Is documentation a valid reason?

Old Linear Technology, Analog Devices, and Texas Instruments data sheets were and are fantastic. Someone with an understanding of little more than the fundamentals of resistors, inductors, and capacitors could learn about and implement a DC/DC converter from those docs - and the simplest ones are the oldest ones.

A seasoned electronics designer with previous examples to draw on can select an IC and basically reverse-engineer it from the sample application and comparisons with previous designs they're familiar with. If they get stuck, they will call their vendor...they might not even read the docs. Hobbyists can't do that.

metafex|6 years ago

I have the most experience with TI silicon, so that's where i can talk most about the datasheets.

Some are excellent, many are really good and except for the odd outlier, most are sufficient. Especially certain lines of the newer dc/dc's have really good datasheets where you can just take the reference circuit in the datasheet as is, plug in your values in the formulas to get your inductance, resistors and cap values. Oh, and webench power designer also does a good job if your application is not too complex.

And complexity is also why i mentioned the simpleswitcher series. Other vendors also have similar simple integrated and modern solutions. With good documentation.

And as for Linear, they have amazing chips and documentation with a price that brings tears to your eyes. I have a love/hate relationship with those.

As for calling up vendors, TI at least has their e2e forum where you usually can get an answer no matter how much you pay them, you just need to create an account.

xondono|6 years ago

I would caution against using LCSC chinese ICs in general, the fact that they are available now does not mean that they will be available 6 months later.

This can work for small productions where you’ll be stocking the full production beforehand, but for open source projects it will be a lot of lost resources.

Other than that, I don’t see any reason for NOT putting 20 year old ICs on boards (as long as they are not on EOL or NRND status). Yes, some newer parts have better tech, and they should totally check them out, in the end is about finding the best fit.