ITEM NAME:NE555+CD4017 Running LED Flow LED Light Electronic L1Y7 nice DIY duction Su F9J2 Description: 100% brand new and high quality Kit Name: NE555 + CD4017 water lamp kit / parts Supply voltage: 2.5--14.5V PCB size: 5.4cm * 2.1cm PCB thickness: 1.6mm Circuit principle: This kit is mainly composed of a clock generation circuit and a decimal counter circuit. The self-excited multivibrator with the NE555 at its core charges the capacitor C1 through R2, R3 and R4. When C1 just begins to charge, the NE555's 2-pin is still at Low, so the output pin 3 is high, when the power by R2, R3, R4 to C1 charge to 2/3 supply voltage, the output pin 3 level from high to low, NE555 internal discharge tube is turned on , The capacitor C1 is discharged through pin 7 of R4, R3 and NE555 until the voltage at both ends of C1 is less than 1/3 of the supply voltage, and the level of pin 3 of NE555 changes from low to high again. C1 is recharged again, This cycle of oscillation. Charging time: 0.695 (R2 + R3 + R4) C1, discharge time: 0.695 (R4 + R3) C1, adjust R4 can control the output frequency of the oscillator, NE555 clock oscillation signal constantly added to 14 feet CD4017, 10 LEDs are connected to the 10 outputs of the CD4017. When the 10 outputs of the CD4017 are alternately high under the action of the clock signal, D1 - D10 are sequentially turned on to form a water lamp effect. Adjust R4 to adjust the flow of LED lights. Package Included: 1x PCB board 1x 2P pin header 2x 1UF capacitor 10x 3mmLED red 10x 1K resistance 1x 2.2K resistor 1x 10K resistor 1x 50K blue white potentiometer 1x NE555 1x CD4017 2 Thank you for your purchase Problems? You can follow below process to chontact us. There is a time zone difference,but we will do our best to quickly response to your questions:.This kit is mainly composed of a clock generation circuit and a decimal counter circuit. Adjust R4 to adjust the flow of LED lights. Circuit principle 10x 1K resistance. 10x 3mmLED red. PCB thickness: 1.6mm.