4020 14 Stage Binary Counter

Here, a 4020 IC is used to light up an LED light every 1 second. This IC does not have a built-in oscillator so that a 555 timer is used to generate clock pulses. In this circuit, the 555 IC generates a 1Hz signal. A 10K resistor, a 68K resistor and a 10µF capacitor are chosen for this purpose. The signal is then sent to the clock input (pin 10) of the 4020. 4020 IC has 11 outputs. In this simple project, only pin 9 is used. Reset pin (pin 11) is connected to the negative terminal of battery with a 100 nf capacitor. A high level at this pin will reset the counter.

When the LED lights are arranged like the picture below and each is connected to the corresponding pin on the 4020 IC, the LED 1 will turn on and off every 1 second. LED 2 will turn on and off every 8 seconds and so on...