Package includes :

• PCB
• 74LS90
• LED – 4
• 1K resistor – 4
• Push button switch

Assemble the circuit as shown in the following image.

Circuit diagram of BCD/Decade counter using 74LS90 is shown below.

Working

Modules required

1. Voltage regulator module
2. Astable multivibrator module
3. BCD/Decade counter module

Step 1 : Power the BCD Counter module from a 5V regulator as shown in the following image.