power supply 3V forward voltage 3.2-3.4 20mA. How many leds can i light up? Need a resistor for that, and how many OHM?

i am a really beginner, i want leds in serial, and i can't figure out what resistor i need even with web calculator, i do not even know if i need a resistor please help me!

samaddon4 years ago
HI! friend ,
so you got 3volts! then you can light 3 led's with that but they will not glow bright and if you need more power you can add a capacitor you should use a 2200 micro farad capacitor and it should Be a dc capacitor ! and you don't need any kind of resistor be cause your voltage is low and resistant will decrease your voltage and a resistor is needed when forexample you have 5 volt's and you have to light only 1 led then you need a resistor case if you will supply 5 volts to a led it will make it hot and after sometime it will stop working ! if you have any more Questions you can mail me at samad@oniworld.in i will be always available there to help you don't be shy to ask! bye! bye!
Your power supply is too small, it won't light these LEDs properly.

Forward voltage is the ideal power supply voltage...at which you'll need to limit the current to 20mA with a resistor. for a 3.4v led, 3v will not light it effectively.