Note: The output is active low and open collector:
- H, Inactive and OFF are same
- Active, L and ON are the same.
- In order to light up LEDs, each LED in the 7-segment display should be wired as shown below.
The 1 K Ω resistors limits the current through the LED to 5 mA.Output1 K Ω
Cathode LED Anode (^) Vcc
74LS 47