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by amluto 1141 days ago
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

1 comments

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.)