Kit De Entrenamiento Soldadura Smd 0805 0603 1206 Sot23 Soic Itytarg

LED flow lamp (CD4017+NE555) consists of a multivibrator composed of NE555 and a CD4017 decimal counter/pulse distributor.

The multivibrator composed of NE555, the power supply DC5V charges the capacitor C1 through resistors R11 and R12. When the charging reaches a certain extent, the voltage of pins 2 and 6 of NE555 increases. When the voltage of pins 2 and 6 of NE555 increases to 2/3Vcc (2/3X5V), the output of pins 3 of NE555 is low.

The 7 pins of NE555 are in a low resistance state to the ground.

The electrolytic capacitor C1 discharges through the potentiometer and the 7 pins of NE555 to the ground. When the voltage of the 2 and 6 pins of NE555 is lower than 1/3VCC(1/3X5V), the 3 pins of NE555 output is at a high level, and the 7 pins of NE555 are in a high resistance state to the ground.The power supply DC5V starts to charge the electrolytic capacitor C1 through R12, and the cycle repeats.

The oscillation period can be changed by changing the resistance value of the resistor R12, that is, the flow velocity of the lamp group.The 3 pins of NE555 output oscillating pulse as the clock pulse of CD4017 work.

Under the action of the clock pulse, the CD4017 decimal counter begins to count.

When the first pulse comes, QO output high level, LED1 lights up.Until Q9 output high level, LED10 light.Complete a loop output, and then carry out the next round of elm output, lit by LED1, LED2.....