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1.5 volt LED? Answered

well im putting an LED to my coilgun so it would turn on when  the gun was on (lol) and i was thinking about putting it "between" the 1.5v battery and the charging circuit BUT! i found out that the f*cking LED is a 3v, I tried with all of the LEDs I have but I think non of them works with 1.5 volts
does the 1.5 volt LED actually exist? (LOL)
or, in the case that I do not find any LED like that one, how could I use the 3v one so it could turn on with 1.5v??

maybe the drawing can help...
help pls

**the circuit has a red led that lights up when the capacitors are charged, this one is just something i thought it would be nice to have to have it and tell you when its on**
**ALSO** this is just a part of the entire circuit, its not the complete circuit, right?, the drawing is just to give an idea of the led part


Ok, yes most 1 lumen solar lights use 1.5 v white LEDs. These lights only have 1 battery which is a rechargable aa or a 2/3 aa. Walmart sells their cheapest solar path light for 97 cents

my question is how are they lighting a string of led lights with 1.5v power supply. Multiple color, solar charger. lasts 8 hours. I do not see them wiring them for joule thief. parallel wiring? 15 -20 lights on one AA battery?

Harbor Freight Tools sells a 50 LED rope of lights powered by a 1.2 Volt NiCd battery charged by a small solar panel.

I am looking for a 1.5 volt DC power supply to make it even simpler, hard wired.


8 years ago

A 3mm RED led might work...

I think there are two solutions: buy a 1.5 volt LED or use a Joule Thief... https://www.instructables.com/id/Make-a-Joule-Thief/

You simply wont get a 3v led to light with 1.5v. You might get a red led (1.6-2.0v) to work, Amber is also quite low. Blue/white/green are virtually out of the question without a boost circuit. You want it as seandogue says, across the circuit, not in series with the circuit -- and that led needs a current limiting resistor or it will burn out. Lastly, check the polarity. LEDS need the correct +- hooked up.

1.5V is pretty low for most leds. The best you can do is look for some small (T-1/8) GaAs leds. with a low forward voltage. They can often be run down to just under 1V with a dim output (at a fractional mA current draw too!), but they're getting a bit harder to find than they once were.

ime, Red will be the most effective at running low.

You *could always drive it *across the circuit instead of in series too...your circuit is not a very effective use of electronics, imo, no offense intended. LEDs aren't designed to be inline regulating devices for charging circuits...

First I would put the led in parallel with the circuit.

Then you could either buy a 1.5 volt led like these at Digikey.


Build and led driver to raise the 1.5 volts up to 3 for the led.