So, the mosfet heats up because of the higher voltage supply, and not the PWM.And because with the "linear" PWM the current goes quickly up and down, this creates the heat
I mix and match. Sometimes a article is cheaper or available in more versions from one of the two. Just look at both although I must say, past year I ordered more from AliExpress then eBay.
I think you have it.When switched on or off little heat is generated.When operated between 0 and 100% it is operating in the linear region where significant heat is generated.During switching it is operating in the linear region and generating heat,, but because the switching time is so fast it is not in the linear region for long.An oscilloscope is not essential but if you want to build a circuit using discretes it is a very useful tool to see what is going on.Most of us had to wait a long time when we started out to get one.I built my own (from a kit.)
AliExpress AliBaba is the greater wholesale brother of AliExpress.Only one problem, you ordered 900mA (or 1000mA depending on which part of the description you believe) drivers but the leds you showed had a max rating of 700mA...
...You could also make a linear current source with transistors which is a lot better then a resistor (who wants a 7W resistor) but that transistor will still produce A LOT of heat. Whaaaa, now I see my quote again I see a terrible typo! Edited the post and here it's correct again:It's a little module. Some links:PT4115 900mAPT4115, probably 600mA, not 100% sure, listing is a bit weirdProbably PT4115, 300mA...
is it possible, some easy way, to limit the current other than changing the resistor?
Also, I am not quite sure how to use this? It has only GND + Vcc?
How can I control it with an Arduino?
I think all these three are based on the PT4115 chip which is a very popular chip. Although most modules don't break the pin out (aka, don't add a solder pad) the chip does support dimming via PWM. Just solder a wire directly to the chip and it's a very easy driver.
I googled a more accurate picture:And does the "crazy" heat come from the PWM?
What do you mean by "connect the removed part"? Do you mean, bridge the solder pads? Then NO, then you'll blow the led. Like I said, it has two parallel resistors, just remove the one and done!
If you take a careful look at that driver board, you will see that it has a PWM input near VIN+. You don't need to switch power with a MOSFET.Perception of brightness is highly nonlinear. Changes in intensity are much more noticeable when at brightness than high. It's the same as our perception of loudness.
I started working on the board now, and I can't find the PWM input near VIN+ ?Are you referring to my 900mA driver?
I think for the PWM I need to solder pin 8 of the IC near the outs?
He wasn't The other module you showed had the pin broken out. The one you have don't. Exactly! See reply #20