I have 18W lamps that came with non dimmable led drivers. Ive found datasheet for the main chip (ws3441), which included schematics:
I'd like to add dimming controlled with PWM - 1024 levels. I already have PWM part ready - used 6W lamps before successully. They also came with non dimable led drivers but I replaced power adapters to one one 20V with enogh power, which was not sensitive to the shorts in the circuit made by MOSFETs controled by microchip. For 18W lamps I cannot find right power adapter - 70V / >2A. Anyways, I plan to mount those lamps in different rooms so one adapter will not be enough. The best solution would be to make use of those drivers that came with lamps. I've read a bit and searched over internet for solution, found few interesting topics, two of them below:
but I dont know how to get use of that information to resolve my problem. Basically Im taking following solutions into account:
- somehow disable current sensing and make it fixed (led driver will only be used with this one kind of lamp) so PWM can work properly,
- maybe using additional transformer like shown here would be solution?
Here are photos of the driver: