Wiring Schematic Diagram

The simple and easy to build on/off LED fade effect circuits included here will specially interest the new electronic hobbyists. Just like the name of the circuit, the light intensity of LEDs in this circuit will fade from high intensity to low intensity and then off.

C 30 uF and R 100k (blue color) control the speed of the fading. You can replace the 100K ohm resistor with 100k linear potentiometer so you can adjust the speed any time. You can make the circuit even simplier by leaving out other of the transistors and those leds that are connected to it. Good for power led pulsing etc.

Op-Amp LM324 Pinout

LM324 is an OP-Amp amplifier. There 4 op amp, and we just use 2 op amp in above circuit diagram. You may use the other 2 op-amp to build another similar circuit. Transistor is BC547 and the led is ultra bright red with 220 ohm resistor in series.