Hi thanks for reading.

Im looking to make a circuit thats simply 5 LED's and an on/off switch powerd by a low voltage high capacity lipo idealy.
I'm not sure on how to set it out or what voltage/resistors i would need.

Thanks for your time!

 

Then probably you will need a simple boost converter since a single LIPO
cell V may not be high enough to drive the 5 LEDs in series. Or are you
going to drive them paralleled ?

Regards, Dana.

 

Then probably you will need a simple boost converter since a single LIPO
cell V may not be high enough to drive the 5 LEDs in series. Or are you
going to drive them paralleled ?

Regards, Dana.

i would prefer parallel incase one of the LED's is damaged, i dont mind useing a stronger lipo, though i wouldnt want to go past 11.1V because size is an issue

 

the Led'sill be useing are
https://www.ebay.co.uk/itm/Ultra-Br...34:m:mn5bDTuofxSG6pySFMbIpzg&var=580526763637
5mm constant

 

Your LED's specs are If(forward current) 20mA, and Vf(forward voltage) 3.0-3.3V. Being that they are purchased from ebay I generally down-rate the specs for safety/longevity. I will calculate based on a If=17mA and Vf=3.0V. I actually do this for all my circuits containing LED's.
With a single 3.7V Lipo, this is certainly doable.

Calculations: (LINK)


In parallel, each LED needs a limiting resistor as seen in the wiring diagram above. 47 Ohm(1/4W) is a standard resistor value and should be easy to find.

 

As Ionic has show with LEDs in parallel you do not need a boost converter,
and your battery is fine.

Regards, Dana.

 

Your LED's specs are If(forward current) 20mA, and Vf(forward voltage) 3.0-3.3V. Being that they are purchased from ebay I generally down-rate the specs for safety/longevity. I will calculate based on a If=17mA and Vf=3.0V. I actually do this for all my circuits containing LED's.
With a single 3.7V Lipo, this is certainly doable.

Calculations: (LINK)
View attachment 169680

In parallel, each LED needs a limiting resistor as seen in the wiring diagram above. 47 Ohm(1/4W) is a standard resistor value and should be easy to find.

thats ace! thanks!

 

thats ace! thanks!

Note: With such a simple design there will be no way to know when your battery is discharged (3.0V) other than some dimming of the LEDs, so keep an eye on the battery so as to not shorten its expensive life!