Re:There's something off about LED bulbs
by novok on Friday March 31, 2023 @12:17AM
(#35382486)
A bunch of this is driven by power efficiency requirements, creating a flickering low quality mess. Like no-flicker LED lights usually have a worse power factor.
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Most flickering mess is caused by throwing away half of the sine wave due to cheaping out on components and has nothing to do with efficiency.
Waveform lighting sells flicker free LED lighting that they can't ship to california due to a lower power factor, and their 15W bulbs cost $29, so it's not a cheap component issue: https://www.waveformlighting.com/home-residential/why-cant-t...
Otherwise why exclude the california market in this case.
Re:There's something off about LED bulbs
by Dylan16807 on Friday March 31, 2023 @02:04AM
(#35383232)
A bulb gets a burst of power every 120Hz, so it would only use about .075 joules per cycle. Half the time is spent above 110v, and half is under 110v, so we need to store less than 1/240th of a second of power to have a perfect output and a perfect power factor.
Let's put a capacitor before the regulator to store that power, and design the regulator to compensate for how the voltage will vary over each cycle. Since we don't want to drain our capacitor entirely, let's spec it for .05 joules at 100v, which means 10µF.
Digikey says a 10µF 200v capacitor costs ten cents.
If there's flicker, I blame the voltage regulator or lack thereof, not the requirement of power efficiency.