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Comment by massaman_yams | Hacker News Reader

Mean Well has some constant current dimmable 24v power supplies with zero flicker. You'd need 2 if you want each strip to be independently controllable. They also can take a PWM signal if you're so inclined, but I bought them because I prefer flicker-free dimming. e.g. https://www.mouser.com/ProductDetail/709-HLG40H-24B

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You are unlikely to get amazing dimming performance using constant current with a 24V strip intended for constant voltage operation.

For a bench application like this, get a constant current strip from Bridgelux. They’re cheap and excellent. Digi-key sells them. The “thrive” series is a bit less efficient but has a very nice spectrum. The tiny drivers from Cuvee Systems work well, start quickly, and dim well, but any ordinary LED driver can drive them. Or the bench power supply :)

For 24V tape, here are a few decent choices for drivers:

The Meanwell PWM series. The frequency is below IEEE 1789 recommendations but is okay.

eldoLED LinearDRIVE. The best, but kind of expensive and annoying to use. Program it for a log curve. Here, for example:

https://www.ll-sales.com/eldoled-lineardrive-212d-dmx-led-dr...

These are convenient but massively overpriced:

https://www.diodeled.com/switchex.html

Yeah, with a CV strip the Mean Wells with CC dimming have an abrupt shutoff at low brightness - maybe 5% (I haven't measured it), and a brief flash upon increasing brightness just above that threshold. Otherwise they work reasonably well for my use case.

Thanks for the additional recommendations.

I would also expect some degree of uneven output at lower currents, especially as it ages. But maybe LEDs are more consistently manufactured these days.

You may also experience worse failure modes with the fancier strips that have current limiting ICs instead of resistors.

(Pixel strips can be quite good, too. They seem to mostly have very high PWM frequencies. I assume this is because the electrical behavior is better that way rather than due to any particular care for the pleasantness of using them.)

Mean Well’s power supplies are by far the best I’ve used. Apart from working really well, they also seem to be constructed better than others I’ve used.

My 3d printer, grow lights, hydroponic automation hardware, and a little CNC project are all run on Mean Well power supplies now.

Mean Well has been around for a few decades. They are in a lot of pinball machines too.

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