Dimming The Undimmable Lights 

I am a retired EE. I really appreciate your level of expertise. Your videos are entertaining, informative, and I almost always leave them saying “I want to build that!”

Other people: It has almost nothing inside, they've skimped on parts, it must be crap. Leo: What a great, price-optimized feat of engineering, it does what it needs to do well at the lowest price point possible, hats off to the designers. It really shows you've designed more than your fair share of products. Anyway, great video, thanks for that! I have to say, I did not expect the synchronization issue at all!

This is the best channel on RU-vid

You could also try and mess with current sense resistors. You can add another resistor in series with already soldered ones and bridge it with mosfet. you must set minimum current with that resistor, and there is no way to turn it completely off, but you should turn off power anyways. It works even better if IC has separate feedback pin, because you can inject current and make it analog dimmable. * Storage inductor may need to be higher value in some cases when lowering current.

Good explanation, good editing, good information = great stuff

It won't be long and you will be huge!! Great Stuff!

Can't wait to see your channel become famous (and I'll feel proud being an early subscriber 😅). With such amazingly high quality contents, you deserve it.

One of the best channels for this type of content. I also happen to build some of your circuits and they do work well!

Huge fan of your engineering attitude. Your videos are not only well put together and entertaining but also very inspiring.

Great job here, you really went in-depth and covered a number of aspects (rather then just hacking a poor solution together). Learned quite a bit and looking forward to more, thanks!

Great video indeed. Very inspiring. What is fantastic is also to get the possibility to understand step by step the engineering process. So a big thanks for sharing

A great video yet again, you really invested effort into the design i love it

Awesome, as usual! And so well explained...

I am not sure how I found your channel. But I am subscribed and I will be watching you previous videos. Thank you for sharing your thoughts on these matters.

I really like your design philosophy. I too like elegant design.

I really liked this and I will do my best to point people your way.

Your channel is extraordinary. I hope you grow.

Wow just the right project. I was doing exactly this project!

I really like you style of presenting, which is both technical and layman to move things along. Personally, the DALI thing is probably more of a deterrent for a lot of us who simply want to convert a non-dimmable LED to dimmable via a standard LED dimmer. Excellent work!

Great video

Thank you from Morocco

Amazing HACK!!

Awesome ❤😀👍👍

Which are DALI's accepted commands and in which format ( frame )? , otherwise, great job integrating the synchronization of the PWM into firmware of the PIC!! Quite great stuff!

Interesting idea to shunt the load in the buck circuit. For me the only solution would have been to replacing the buck ic with a roll-my-own.

If you just need high/low setting for your dimmer, you can dim many non-dimmable LED bulbs with just a capacitor. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-JH68wBXO5j0.html If your LED driver dies, on some light fixtures, you can replace the driver board with a simple capacitor dropper LED driver circuit. You can then switch out capacitors to control the brightness level. You can also change the value of the current sense resistor on the LED driver circuit, to control the LED brightness level.

It would be interesting to see how the 120VAC version of the LED power supply differs from the 230VAC version. Likely only a couple component changes, unless there are any regulatory issues that cause a larger change.

Hi, Leo. Thanks for the content. Do you think it would be worth it to build the whole driver from scratch to be dimmable ? It looks to me that, after including another power supply and a microcontroller, it would be easier to make the microcontroller control a current regulator directly, right? (Im a young engineer with little experience) =D

Thank you for this excellent video! What's the purpose of R6 (510k) in the current source that drive the opto's LED?

Thanks again ! It's a wonder video. I have very little knowledge about AC circuits so I will probably need to learn more before implementing it, but I definitely have flickering chinese LED strip that I'll try to fix once I understand more. Quick question : how this kind of display of schematics of big manufacturer plays with patents laws ? Is it okay as long as you don't reproduce the circuit and sell it ? I'm clueless.

What about using a optocoupler to change the led linear regulator current sense resistor(s), then only one optocopler is needed per lamp if your controlling more than one? much less parts and rework? Thanks for sharing!

Elegant design, can you tell me who manufacturers LED.

I had to watch this twice but the "light went on" half way through the second view. Great hack...

Can't we just modify RS1 and RS2 values to adjust the current?

The problem with DALI protocol, the switch also needs Line *AND* Neutral, which usually not the case (normally only the line is present at the switch). THEN it needs 2 more low voltage wires which you need to run separated from the high voltage. So a simple retrofit is almost never possible. To address this problem, I use the switch with an IKEA wireless dimmer (TRADFRI) which costs about 6USD. So I switch the light on-off, and I dimmer it independently if I want lower settings. Would love to see you also incorporating some kind of radio solution. Besides a matching DALI switch (just the switch itself, Berker 2858) costs about 92USD where I live. And I would also needs some remodelling for retrofit(getting Neutral to the switch and also low voltage wire routing), which is price prohibiting. One switch retrofitting would easily costs me about 1000USD at least. So a 6USD RF IKEA dimmer is a better way for my case and I think for most of the others too. What do you think?

Where are you. People still watch your videos. I hope you're doing ok.

Nice hack , and very good documentation and presenting However , I think the dimming part is a little bit over engineering , considering the original control is done using this three pin KP1050A device . You already mentioned the original feedback resistor in the 3 pin dimming circuit . Wouldn't it be much easier to alter this resistance value instead of a new pwm circuit ? My idea is replacing the original current feedback resistor with lets say some other resistors and making a dimmer shorting accordingly these resistors . It may not have continuous dimming but for more people a few steps dimmer is more than enough. I think it would work OK and would be simpler . Considering the DALI interface needs extra wiring , a retrofit project would perhaps benefit more from a wireless interface , like a BLE controller .

I love your channel the ONLY criticism I have is that, as a novice, I feel you are too quick sometimes when explaining the electronics because it is so easy for you, you have forgotten us aged poor souls who need to slower explanation before they grasp a concept.

First time seeing this kind of "sliced up solid pcb tinned" smt method. Maybe you could talk about that. Great videos - a chance to learn from a master.

Why can't we just play with the CS pin?