i'm just surprised it works without any resistors and the current is staying pretty average around 25mA and they are super bright and barely any warmer than ambient room temperatures
I thought they would just instantly go BANG as soon as they get attached because they have no resistor
I thought they would just instantly go BANG as soon as they get attached because they have no resistor
Your question is unanswerable unless you post Brand/Model/Datasheet so we can see the V/I curves.and they dont burn up.
So please do.
* Brand
* Model
* link to datasheet
otherwise your question is incomplete .
3.2Vf across each of the three LEDs accounts for 9.6Vand they dont burn up. ive had them running for 2 days and the current is only about 25mA and the LED's are rated for 30mA
I tried it just to see what would happen and it works pretty good
Subtract that from the 12Vdc supply and you have an excess of 2.4V.
If only 25mA flows, then you have an effective resistance of ~96ohms (2.4V/0.025A)
Where is your 96ohms hiding?
It's there !!!
and they dont burn up. ive had them running for 2 days and the current is only about 25mA and the LED's are rated for 30mA
I tried it just to see what would happen and it works pretty good
Look Mom no hands
Which only proves you have a stable 12V source and the LED temperature is at equilibrium. Besides that, parts don't let out the majick smoke once they hit some "rating" number.
Take a heat gun on those LEDs and watch the current. I'll bet you can see 'thermal runaway in action.
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why would I want to take a heat gun to them? that would just be stupid and a waste of good LED's
they are chanzon warm white straw hat LED's from amazon
Chanzon 100 pcs 5mm Warm White LED Diode Lights (Clear Straw Hat Transparent 3000K DC 3V 20mA) Super Bright Lighting Bulb Lamps Electronics Components Light Emitting Diodes - - Amazon.com
3 to 3.2v
very good quality I have an array of 36 and I can give the array 2 amps for about 10 seconds and the LED's are only a bit warm and not hot so they work good as a photo light to take photos of miniature scenery with the warm white color the array of 36 can handle 1 amp continously they stay cool for hours (barely a degree above ambient temperature.)
I have a power supply with constant current function to power the LED's I was just testing something with them.
they are chanzon warm white straw hat LED's from amazon
Chanzon 100 pcs 5mm Warm White LED Diode Lights (Clear Straw Hat Transparent 3000K DC 3V 20mA) Super Bright Lighting Bulb Lamps Electronics Components Light Emitting Diodes - - Amazon.com
3 to 3.2v
very good quality I have an array of 36 and I can give the array 2 amps for about 10 seconds and the LED's are only a bit warm and not hot so they work good as a photo light to take photos of miniature scenery with the warm white color the array of 36 can handle 1 amp continously they stay cool for hours (barely a degree above ambient temperature.)
I have a power supply with constant current function to power the LED's I was just testing something with them.
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why? IDK, to learn stuff. No not Stupid. you could use a lil finesse , rather than global heat soak.why would I want to take a heat gun to them? that would just be stupid and a waste of good LED's
Heat gun and freeze spray is standard stuff in any electronics lab.
full disclosure.I have a power supply with constant current function to power the LED's I was just testing something with them
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