Simple Flash Circuit Production 5MM LED Bead Flashing DIY Kit Flash Circuit Board ModuleItem NO.: 5MM LED Kit

LED Beads Flashing DIY Kit

Function Introduction:

After turning on the power, the left and right red LEDs (which can be replaced with other colored LEDs) flash alternately. After repeated cycles, the higher the power supply voltage, the brighter the LED. Changing the capacitance value of the electrolytic capacitor can change the speed of alternating flashing. The larger the capacitance value, the slower the flashing speed. The smaller the capacitance value, the faster the flashing speed. The circuit is simple and easy to understand, and the solder pad has been treated with tin spraying technology, making welding easier and the solder joints more beautiful! Especially suitable for friends and students who are new to electronics.

Circuit principle:

As soon as the power is turned on, the two transistors must strive to conduct first, but due to differences in components, only one transistor leads the way. If the Q1 lead is turned on, the Q1 collector voltage drops, D1 is lit, and the left end of capacitor C1 is close to zero voltage. Since the voltage at both ends of the capacitor cannot suddenly change, the Q2 base is also pulled to approximately zero voltage, causing Q2 to cut off and D2 to not light up. As the power supply charges C1 through the resistor R2, the base voltage of the transistor Q2 gradually increases. When it exceeds 0.6 volts, Q2 changes from a cut-off state to a conduction state, the collector voltage decreases, and D2 is illuminated. At the same time, the decrease in collector voltage of transistor Q2 causes the base voltage of transistor Q1 to jump down through the action of capacitor C2, causing Q1 to change from conducting to cut-off, and D1 to extinguish. In this cycle, the two transistors in the circuit take turns conducting and cutting off, and the two light-emitting diodes continuously cycle and emit light. Changing the capacity of the capacitor can change the speed of LED cycling.

Component List:

1/4W resistor 510R * 3

1/4W resistor 33K * 3

5mm plug-in LED F5 * 2

Electrolytic capacitor 22uF/25V * 2

Insert transistor 9014 * 2

Public to female DuPont line 10cm * 2

PCB board * 1