7 Segment LED Counter Circuit

Schematic -

7 Segment Reference -

Parts List -
R1-R7 - 7 - 470 Ohm 1/4 Watt Resistor
U1 - 1 - 74LS90 TTL BCD Counter IC
U2 - 1 - 74LS47 TTL Seven Segment Display Driver IC
DISP1 - 1 - Common Anode 7 Segment LED Display
MISC - 1 - Board, Sockets For ICs, Wire

Notes -
1. All pulses to be counted are to be TTL compatible. They should not exeed 5V and not fall below ground.

2. You can add more digits by building a second (or third, or fourth, etc...) circuit and connecting the pin 11-6 junction of the 74LS90 and 74LS47 to pin 14 of the 74LS90 in the other circuit. You can keep expanding this way to as many digits as you want.

Posted in: LED counter