Basic LED question

Hi people, first time poster here. I love playing around with electronics, i know enough to do my job, but not enough for my hobby..

I want to use a total of 20 LED's running on 3V (2x AA battery) 6 bright white 6 diffuse red 8 blue ones (and a switch somewhere to break the circuit)

Its basic, IF you know how to do it.. I have loads of resistors and LED's, breadboard and leads right now but how do i know where to even start??

Any help is appreciated :)

by ElectroDuck
October 14, 2019

With only 3v power supply about the only choice is each LED with its own series resistor and all connected in parallel through a switch to the power supply. However; LED's are very non-linear devices and don't pass current until something around 2.5 to 3 volts. Once above this level a small change in voltage, temperature or LED v/i curve makes a large change in current risking burnout of the LED. The usual answer to this is to use a higher voltage (5v or more) and a series resistor, say 100 or 200 ohms. This works because the current is then controlled mainly, but not completely by the resistor.

by Foxx
October 19, 2019

1 Answer

Answer by estelleslighting

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+1 vote
by estelleslighting
October 15, 2019


by ElectroDuck
October 16, 2019

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