I have several rolls or LED tape lighting. The lights need to be dimmed with a RF controlled dimmer, which is a leading edge (triac) type dimmer.The specifics for the lights is limited but here is what I have:
-The lights are intended for a constant voltage (12v) power supply
-When hooked up to a 12v power supply it draws about 2A
-Each led has a resistor associated with it but the tape is covered in a
plastic coating for protection and I can't see the circuit layout.
-The roll is pretty long and has a bunch of LED's on it. I haven't counted all
of them yet
So long story short, I got this to work quit well but there is a problem.
To get this to work I connected the the dimmer to a 10:1 transformer from there I connected the secondary to a rectifier and on to the LED. At first this would not work, by this I mean that the lights would pulse in a dimming fashion. I then hooked up the O-scope and checked a few points. I found that the signal was severely messed up. Basically there was no stable output from the dimmer circuit.
So I had an idea, maybe the dimmer circuit is looking for a load (lightbulb). I got the idea to wire up a standard incandescent in parallel with the primary side of the transformer. TADA it works. The output from the dimmer circuit became steady and I could monitor the leading edge shift with the adjustment of the dimmer. The LEDs dimmed perfect with no flicker and seem to have a pretty large range of diming.
PROBLEM:
Who wants to run a lightbulb when the goal is LEDs. So this is where I am stuck. What can I do to take that lightbulb out of the mix. Oh I even tried replacing the lightbulb with a resistor and that also worked but same I^2R problem as the lightbulb.
Any suggsted circuits or reading or ideas would be a great help
Thanks very much
-The lights are intended for a constant voltage (12v) power supply
-When hooked up to a 12v power supply it draws about 2A
-Each led has a resistor associated with it but the tape is covered in a
plastic coating for protection and I can't see the circuit layout.
-The roll is pretty long and has a bunch of LED's on it. I haven't counted all
of them yet
So long story short, I got this to work quit well but there is a problem.
To get this to work I connected the the dimmer to a 10:1 transformer from there I connected the secondary to a rectifier and on to the LED. At first this would not work, by this I mean that the lights would pulse in a dimming fashion. I then hooked up the O-scope and checked a few points. I found that the signal was severely messed up. Basically there was no stable output from the dimmer circuit.
So I had an idea, maybe the dimmer circuit is looking for a load (lightbulb). I got the idea to wire up a standard incandescent in parallel with the primary side of the transformer. TADA it works. The output from the dimmer circuit became steady and I could monitor the leading edge shift with the adjustment of the dimmer. The LEDs dimmed perfect with no flicker and seem to have a pretty large range of diming.
PROBLEM:
Who wants to run a lightbulb when the goal is LEDs. So this is where I am stuck. What can I do to take that lightbulb out of the mix. Oh I even tried replacing the lightbulb with a resistor and that also worked but same I^2R problem as the lightbulb.
Any suggsted circuits or reading or ideas would be a great help
Thanks very much