I have the same driver and I have a problem becouse in low and medium mode led blinks a little every (i think) 5s. It is not any protection feature, and PWM. In high mode all is ok, only in low and medium something like this is happening.
If you don’t mind me going on a bit about this, how about some 100µF (tantalum SMD) for each Ampère at 1 KHz? (loosely based on 1000µF for 1 A at 50 Hz)
Or would it trouble the FET?
I assume it would be better for the LED and for its efficiency.
Soldering looks pretty sloppy, efficiency is rather weak (talking about all modes). I also have one of those and blinks randomly. I have one with a big inductor that also does 5A and that one always get hot to 105C and output drops immediately to low mode. I am sure these drivers are random as random they can be. I do not know why they choose such small inductors for such currents and I am sure that one is not a high-end inductor for it's size.
A 7135 does not use pwm, but most drivers using a 7135 adds pwm. The pwm can be anywhere from 100Hz up to above 10kHz.Using a high pwm frequency with the 7135 do have some problems, because the 7135 is not that fast to turn on, especially not when driving a pack of them from a single microprocessor output pin.
Here is an example from one of my driver tests:
The microprocessor has its output on for nearly 2us, but the led is only on for about 0.1us. The rest of the time is used for the 7135 to turn on.
Really?
So, just to verify, a 7135 just burns off excess voltage?
Like when you run a LED on 3 Volts, from 6 Volts battery, with one 7135, the 7135 uses as much power as the LED??
:^\
I wouldn’t trust a DMM’s view on the average voltage.
For the rest this is all a bit over my head…
I find it hard to believe though that a, say, 100kHz PWM-ed power supply can’t be smoothed to its average with a coil and a capacitor, like a class-D amp loaded with a speaker.
How about this cute thingy to modify into a driver?
Probly not, but it’s tiny enough!
I cant tell you how many times Ive torn apart budget flashlights and thought the exact same thing about the chimps that must have put them together. Its sad that so many people have absolutely no pride in their work or such justifiable disdain for their sweat-shop employers.
As always, thanks for the excellent review. I almost purchased one of these cursed drivers but didnt when lck-led’s customer service refused to answer my email questions.