Is a resistor needed for LEDs in this beatbox project?
1069
Correct formula for LED current-limiting resistor?
48777
Resistor requirement for 3.3v
53976
How to connect an LED indicator to a circuit?
93477
Does LED brightness change with voltage?
140532
LED as power generator
125392
Is LED properly implemented in the constant current circuit?
132473
Identifying a resistor with a weird band combination
23708
Resistor in series
156325
Pull-up resistor clarification
51708
Why do LEDs not obey Ohm's law?
133986
Multiple two pin multi-color LEDs pattern - how does this work?
136371
Mains doorbell to Arduino
153812
Resistor value for Opto-coupler input
31944
How do I model an LED with SPICE?
142361
Do I need a base resistor for a BJT?
33926
Calculating resistor value and power rating for LED driving
16242
How do two-leaded color changing LEDs work?