Seven Segment Counter Circuit

Seven Segment Counter Circuit is one simple circuit.

It count numbers and show on seven segment display.

When we press button number goes up by one.

It is very easy to make and good for learning how counting works in electronics.

What is a Seven Segment Counter Circuit:

Seven segment counter circuit is small electric setup which counts numbers and show on seven segment display.

This display are having 7 parts which look like number “8” and each part is called a, b, c, d, e, f, g.

By turning on some parts it will show number from 0 to 9.

And these numbers show one by one when circuit works.

Circuit Working:

Parts List:

Seven segment display have LED parts in shape like number “8”.

When signal come to input pin, right LED light up and show number from 0 to 9.

These displays also used in LCD and many circuits to show number or data.

They work with low voltage and come in two types: cathode and anode.

This article show how to make simple seven segment counter using 555 IC, 4026 IC and common cathode LED display.

When we press count button 555 IC make one pulse.

It work like monostable multivibrator.

IC 4026 take this pulse and counts it and show number on display.

Switch button is connect to 555s trigger pin.

When we press it, it give negative signal to start pulse.

How fast pulse come is control by resistor R2 and capacitor C1.

Pulse also goes through resistor R3 and capacitor C2 for stable signal.

This pulse goes to 4026 IC which turn ON right LED parts and show number.

Each time we press the number goes up.

It we count from 0 to 9 and then start again we can press reset button to go back to 0.

Formulas:

We can make seven segment counter circuit using parts in diagram above.

Main parts are 555 IC for clock pulse and 4026 IC for counting and showing number on display.

Below is how to design this circuit.

555 IC as Astable Multivibrator:

This IC gives clock signal to 4026 counter.

How fast it send pulse is control by two resistors and one capacitor connect to it in astable mode.

Frequency Formula:

f = 1.44 / ((RA + 2RB) × C)

where:

• RA and RB are two resistors connected to 555 IC.
• C is one capacitor between pin 1 ground and pin 6 threshold.

Use this formula to get correct values for RA, RB and C to make pulse timing right.

How to Build:

To build a Seven Segment Counter Circuit follow the below mentioned steps:

555 Configuration:

• Connect pin 8 of 555 IC to positive power.
• Connect pin 2 and pin 6 together then connect to ground.
• Connect pin 5 also to ground.
• Connect pin 4 to pin 8 using resistor R1.
• Connect pin 2 to ground with capacitor C1.

4026 Decade Counter:

• Connect pin 13 and pin 14 to positive power.
• Connect pin 15 to ground.
• Connect pin 1 to positive power.
• Connect pin 5 to pin 3 of 555 IC.
• Connect pins 2, 3, 4, 7, 10, 11 and 12 to seven segment display to match the segments
• Connect pin 6 to ground using resistor R2.
• Connect pin 7 to positive power.
• Connect pins 8 and 9 to ground.
• Connect pin 16 to positive power.

Timing and Button:

• Put push button between pin 2 of 555 and ground.
• Connect capacitor C2 and resistor R3 between pin 6 of 555.
• Connect middle point of R3 and C2 to ground.

Power:

• Give power to the circuit with positive and ground connected to power source.

Reset Button:

• Put reset button between pin 6 of 4026 and ground.

Testing:

• Turn on power.
• Press push button to make display count.
• Press reset button to go back to 0.

Important Note:

• Be careful when touching parts and check all wires and pins two times.
• If anyone is new to electronics ask someone with good knowledge to help.

Conclusion:

This Seven Segment Counter Circuit is very useful in digital devices like timers, counters and number displays.

It is one important part in digital electronics.

References:

Frequency counter

Using a Frequency Counter