Unbranded LED tube switchmode driver output.

There is about 140v DC being kicked out by this tiny little switch mode power supply but I have the scope AC coupled so were are only seeing the AC content.
As you can see it's quite poor with a massive 100hz ripple of nearly 30v peak to peak and superimposed on that waveform is 17khz worth of noise which is roughly 800mv peak to peak.
Not very good :)

Driver was under the full load of the LED's.

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Ash

[13 Mar, 2019 at 06:07 PM]

I assume the lower border of the wave is when the LED string stops conducting (Vfwd x number of series segment leds). So the flicker of this one is maybe not as bad, compared to a few where the LEDs actually stay off for some continuous time in the cycle (the ones without any capacitance, not in the primary and not in the secondary)

About the HF ripple - that does not matter from lighting perspective, but 17khz - That is shockingly low, it is within audible range (for young people anyways and definitely for most pokemon) - It would be driving nuts anyone that can hear the coil whine

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