Those bulbs are actually not made by Yuji LED. They are OEM bulbs from LEDISUN which I have several of them myself (5 watts version only). It was out of stock for a long time for unknown reasons (I saw some report that they have no profit for several years already). LEDISUN’s spectrum is rather mediocre comparing to other Ultra High CRI LEDs however they have several patents in Quantum Dot LEDS and they have acquired license from CREE for the “remote phosphor” technology. Combination of Quantum Dot and “remote phosphor” would considerably improve the expected lifespan for LEDISUN lightbulbs (in theory of course, and the main reason that LED bulbs die is the crappy drivers).
I am so upset But it was this company and SORAA that were the inspiration for the creation of my light bulbs for eyes in 2017! And now YUJI is releasing shit with a blue peak This is outrageous and offensive!
Thanks Sunlike, I already read your article. So one quick question regarding Qihan power supplies: the manufacturer told me that 12-20w BP cannot go under 400ma while output 36v however it looks like you managed to make them work with around 350ma (correct me if I am wrong). Are they working fine with 350ma output?
what 20w led driver you mean? 20w dimmable only 300mA, and it can be 400 and 250mA. All my tables you can find here — Telegram: Contact @resistorSunLike
I agree that CBB are much more reliable but I had to live with the limited space inside the radiator. Besides I use MLCC to compensate for the capacitance required and technically they have much longer lifetime comparing to Electrolytes. (Of course, X7R and plus). Add CBB to the output is probably OK but definitely not 2.2uf or 4.7uf ones since the output stage is a one-stage Valley Fill Passive PFC circuit which I still do not understand how that works. https://www.ti.com/lit/ds/symlink/lm3445.pdf
From page 19-20 typical applications. The is the detailed data sheet for LM3445, which this driver uses
For the first pic the output capacitor has to have a voltage rating over 400v (valley fill circuit requirement) so may be I can parallel 0.47uf CBB next to the output electrolyte. For MLCC next to the input caps I used 630v rated ceramic and never expect them to have the same capacity under load. (As long as they do not explode I am happy with then). I usually mod High Power Factor LED Drivers (CE rated of course) and put a modded ripple remover in between. Perfect solution for both Power Factor and flicking.
For Ceremic capacitor you ONLY want to use X7R since they have higher temperature range –55 to 125 degrees and way less capacitance drift compared to X5R. But you still need to at least double the capacity when substituting electrolytes for MLCC. Like 20uf ceramic for 10uf electrolytes. TDK did some experiments regarding all ceremic capacitor LED drivers and they find that they need at least double the capacitance in order to completely remove the flicker. (It has something to do with the response curve and capacitance drift, anyways it is very complicated)
Unfortunately their shipping costs are a big deterrent, 60USD for 4 lightbulbs, they said there are no more affordable options.
I would guess these high shipping costs are high to encourage distributors to carry their products, not retail sales?
One could say these are pandemic shipping costs, but 1 year ago the shipping was the same.