Posts made by Edwin De Bock

I just tested 2 led types with no flicker on my attiny circuit.
It is funny, the expensive leds like from philips: Dimmable 3.8W Warm White have a flickering behavior .
A cheap one available in Action from LSC 6.3W, Dim to Warm and 460 Lumen has no flickering behavior.
Another one from Osram Par 1650: 5.5W Dimmable Warm White, 350 Lumen also has no flickering.
The philips has the best Energy savings though : 4kWh compared to 7kWh for the LSC one.
Is there a relation between energy savings and dim quality ?

Hi @jimmyjames , I try to make a multi channel dimmer by myself based on your circuit.

So I want to use a shared 12V power supply that galvanic separated from mains for my dimmers and also a shared ESP32. But when I read these comments I can not use a common gnd for both channels? Is there a solution for this. So I don't need to have for every channel a different power supply?

With the attiny84 I have a dimmer as well. With this design I can make multi channel dimmers because the mains is completely isolated from the DC part.
See picture:

Another advantage is that the I2C addresses can be programmed in the attiny so I am not limited in the number of addresses.
But when testing this approach I have not that good results in the low dimming , my led bulbs are flickering. So I want to try if the fl5150 is doing a better job.
The flickering starts if I am dimming at 15% .
See the oscilloscope pictures:

First one is if I dim at low percentage then the flickering starts.
The second one is at a level when flickering stops.

Do you think the FL5150 will do here a better job, or can my circuit of the attiny84 being improved to get the dimming correct at the lower levels?

BR,
Edwin