Seven Segment LED Counter with CD4026

Description


This simple circuit counts pulses on a seven segment LED display, and has a maximum count of 9. A CD4026 counter chip counts the pulses and also drives the display. No resistors are required, unless the display is too bright. You can easily add more digits to expand the counting range.

Circuit Diagram


Seven Segment LED Counter

Parts List


Part QTY Description Value
R1 1 1/4 5% RESISTOR 10K
U1 1 COUNTER/ DISPLAY DRIVER CHIP CD4026BE
DISP 1 COMMON CATHODE SEVEN SEGMENT LED DISPLAY  

Construction


This circuit can be constructed on perf board, an etched PCB, or a breadboard. The count input needs to be logic level. To reset the counter to 0, bring the reset input high (+5v) momentarily. To add more digits, connect pin 5 of the first IC to pin 1 of the second IC, and connect pin 15 on the first IC to pin 15 on the second IC. Only the first chip needs a 10K resistor on the reset pin to keep it low.

If you are going to use a switch for the count input, you will need a switch de-bouncer circuit.

For more info on seven segment displays read this article.

 

Circuit: