LED Circuit - How to wire 12 LEDs to 2 AA batteries?

MisterBill2

Joined Jan 23, 2018
18,176
I do not need to build a non-documented circuit to know that different color LEDs have quite different forward voltages, and that as a result, if they are connected in parallel thet will have much different brightness levels. And in the video presented they all looked yo be very bright. And the current versus voltage means that red LEDs will be lighting at about 1.2 volts while the white ones do not light much below 3 volts. That is why I quite agree with AG,that something is not at all right.
 

Audioguru again

Joined Oct 21, 2019
6,674
I have many very inexpensive solar garden lights that use a similar circuit in an IC that steps up the voltage of an AAA Ni-MH rechargeable cell and has a switch circuit to turn on the LEDs when there is darkness and switch them off but turn on the solar panel charger when there is light. It does not use a nail, it uses a small inductor that looks like a 1/4W resistor.
It would probably burn if it tried to drive 24 or 30 LEDs. I have a few driving 2 LEDs brightly.
 

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Tonyr1084

Joined Sep 24, 2015
7,853
I watched that video and it never showed the actual circuit used. And when I paused to try to see the circuit some stupid still shot pops up. So as I see it the whole presentation is suspect and not very believable. Certainly a stepup switching regulator is possible, but with no circuit presented it smells rather fake.
Is this the screen shot you wanted to get?
1612545581747.png
 

Audioguru again

Joined Oct 21, 2019
6,674
The guy who made the video cannot count. How many LEDs? 24 or30?
Isn't the 5.6k resistor actually 270 ohms?
Do the inductors look like 82uH? I see no grey and no red.
If some 2V red LEDs are in parallel with some 3.4V blue LEDs then which LEDs do not light?
 
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