7 Segment Counter using IC 555 and IC 4026

electronics

ByJayant 63

7 Segment Display Counter using IC 555 Timer IC

Digital counters are needed everywhere in this digital world, and 7 segment display is one the best component to display the numbers. Counters are needed in object/products counters, digital stopwatches, calculators, timers etc. To use the 7 segment with ease, there is a 7 segment driver IC which is IC CD4026, so we are building 7 segment counter circuit using 4026 IC.

 

IC CD4026

4026 IC  is a 4000 series IC. It is a CMOS seven-segment counter IC and can be operated at very low power. It is a decade counter, counts in decimal digits (0-9). It is used to display numbers on seven segment displays and it increment the number by one, when a clock pulse is applied to its PIN 1. Means more the clock pulse rate, faster the numbers change in 7 segment Display. Below is the pin diagram and pin description of 4026 IC:

IC 4016 Pinout

 

Pin number

Name

Description

1

CLK

Clock in, Increment the counter with each Positive clock pulse (LOW to HIGH).

2

CI

Clock inhibit - when low, clock pulses increment the seven-segment. Freezes the counter when HIGH, active HIGH.

3

DE

Display enable- chip will be ON when this pin is HIGH, and OFF if it is LOW.

4

DEO

Display enable out - for chaining 4026s

5

CO

 The CARRY-OUT (Cout) signal completes one cycle every ten CLOCK INPUT cycles and is used to clock the succeeding decade directly in a multi-decade counting chain

6

F

Connected to ‘f’ of the 7 segment.

7

G

Connected to ‘g’ of the 7 segment.

8

VSS

Ground PIN

9

D

Connected to ‘d’ of the 7 segment.

10

A

Connected to ‘a’ of the 7 segment.

11

E

Connected to ‘e’ of the 7 segment.

12

B

Connected to ‘b’ of the 7 segment.

13

C

Connected to ‘c’ of the 7 segment.

14

UCS

Ungated C-segment - an output for the seven-segment's C input which is not affected by the DE input. This output is high unless the count is 2, when it goes low.

15

RST

Reset PIN, active HIGH. Reset the counter to 0 when HIGH.

16

VDD

Power supply PIN

 

Above table explains the function of each pin of IC CD4016 clearly.

 

Seven Segment Display

It consists 8 LEDs, each LED used to illuminate one segment/line of the unit and the 8thLED used to illuminate DOT in 7 segment display. We can refer each line/segment "a,b,c,d,e,f,g" and for dot character we will use "h". There are 10 pins, in which 8 pins are used to refer a,b,c,d,e,f,g and h/dp, the two middle pins are common anode/cathode of all he LEDs.

 

IC 4026 is used to drive common cathode 7 segment display. In common cathode 7 segment display cathodes of all the LEDs are connected together, and all the positive terminals are left alone

seven segment display pin diagram

 

Components

  • 555 timer IC
  • 4026 IC
  • Common cathode 7 segment display
  • Two- push ON, push OFF button.
  • Resistors – 10k (3), 100k
  • Capacitor 1uF, 22uF

 

7 Segment Counter Circuit Diagram & Working Explanation

555 Timer 7 Segment Display Counter Circuit Diagram

Circuit is quite easy and self-explanatory, we have interfaced the 7 segment to the 4026 IC, PIN 4,5,14 are left open as we haven’t used them, PIN 15 used to Reset the counter with the help of a PUSH button Switch. PIN 2 is kept LOW to avoiding the freezing and PIN 13 is kept HIGH to enable the IC.

 

Now, the another main component of this circuit, other than IC4026, is 555 timer IC. 555 timer is used here to provide the clock pulse on each Button Press, whenever we press the button the counter advance by one. 555 Timer IC is used here in Monostable mode, to know more, go through this article 555 Timer Monostable Multivibrator Circuit.

 

We have also used a RC circuit (22uf capacitor and 100k resistor) at CLOCK PIN 1 of 4026, so that it only counts one clock pulse on each time button is pressed. Otherwise circuit may behave unexpectedly OR it can count two or more pulses because of noise or bouncing effect of Push button.

Video

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Comments

  • Red Viaje's picture
    Red Viaje
    Nov 03, 2015

    Hi! I built this circuit but when I press the count button, it just goes to 1 and never goes beyond that after pressing it again. And when I press the reset button, it resets to 0 but if I press the count button again it doesn't work anymore. What do you think is the problem? :( Thanks.

  • Luqman's picture
    Luqman
    Aug 03, 2016

    Same when i press push button show in segment 0

  • Harshad Dhane's picture
    Harshad Dhane
    Nov 12, 2015

    My counter is showing 0 only I pressed the buttons nothing happened

  • Jayant's picture
    Jayant
    Nov 14, 2015

    The circuit is working perfectly, please double check your circuit connections specially connections to the seven segment display and only use COMMON CATHODE type seven segment. Take the help of bread board circuit Image.

  • Carl's picture
    Carl
    Oct 10, 2017

    Actually you can use a COMMON ANODE 7-Segment Display but you need to reverse the polarity of the battery and the capacitors or the polarized things in the circuit. I've tried it myself and the circuit works perfectly. Hope it helps..:)

  • Jed's picture
    Jed
    Mar 10, 2018

    I bought an Anode by mistake (newbie), and i was thinking of reversing, just had to check the comments to see if its possible, and here i found and I want to ask if by reversing, only the ones with polarity right? battery, capacitors but the circuit map/diagram remains the same?

  • johnson's picture
    johnson
    Jul 21, 2018

    please can u draw a circuit on how to reverse it when using common anode display?

  • ARUN KUMAR K P's picture
    ARUN KUMAR K P
    Nov 14, 2015

    thank u circuit is working ...

  • akshay's picture
    akshay
    Nov 19, 2015

    thank you!
    the circuit is working perfectly.

  • ibtisam's picture
    ibtisam
    Nov 29, 2015

    Pls help circuit not working

  • Deepak kewt's picture
    Deepak kewt
    Dec 11, 2015

    This circuit not work properly counting process is generator randomly

  • usama's picture
    usama
    Dec 15, 2015

    this is good but you must apply ground terminal

  • Abhishek's picture
    Abhishek
    Dec 17, 2015

    Ground sign is not needed as we are using battery symbol, and Ground is considered as the negative terminal of Battery.

  • steven's picture
    steven
    Dec 19, 2015

    I just made the circuit the 7 segment display turns on but on my design i made just made two holes for the switchs and idk how to play the 4 legged switchss on the board pls help me thank u

  • steven's picture
    steven
    Dec 20, 2015

    Reset button works but the press button to go up to 9 does not help pls

  • Maddy's picture
    Maddy
    Jan 01, 2016

    Recheck the circuit connections, specially from 7 segment to IC 4026

  • HTM's picture
    HTM
    Mar 12, 2016

    I tried so many times but

    1. IC CD4026 becomes hot every time
    2. when i press the button no change occur in the display

    I checked the connection but everything is ok. what is the problem? plz help me.

    * i used 9 V DC Adapter

  • Abhishek's picture
    Abhishek
    Mar 28, 2016

    What is the current rating of your adapter, it should below 500mA. Use the simple 9v battery, shown in figure.

  • gea's picture
    gea
    May 05, 2016

    what should be the schematic diagram if i will do the countdown and i will not use buttons? hoping for your reply. thank you.

  • Abhishek's picture
    Abhishek
    Aug 13, 2016

    You need to connect the 555 in astable mode to automatically provide pulse to 4026 IC, then you dont need button to increment the counter, it will be incremented automatically.

  • andy mackay's picture
    andy mackay
    Jul 14, 2016

    Hi guys, I have been experimenting with this ic 4026 for a couple of days, and when I finally got it working, the numbers were just spinning around very quickly and just displaying random numbers, I was just using a debounce circuit, and not the 555 as you have here. But what I found was that as soon as a jumper was connected to the same track as pin 1 (the clock pin) the 7 segment display would take of running thru the numbers very quick, even if I just touched the pin 1 with the metal prong of the jumper this was enough to set it going, which I assumed was something to do with capacitance from the bread board, to stop it I used a large value resistor.

  • aasas's picture
    aasas
    Sep 12, 2016

    what if i want to use 2 seven segment display?i want to use it as a timer ... in minutes
    will this work?

  • Parth doshi's picture
    Parth doshi
    Oct 01, 2016

    What if I have to count 2 digit numbers ....and display on 7 segment

  • Abhishek's picture
    Abhishek
    Oct 06, 2016

    @aasas @Parth: To use two 7 segments, use another 4026 chip and connect the CO pin of first 4026 IC to the CLK pin of second. Check the use of CO pin in IC.

  • Nil's picture
    Nil
    Oct 18, 2016

    Can see full image of circuit.
    & where are those two wires connected

  • Venkatesan v's picture
    Venkatesan v
    Nov 24, 2016

    Sir i need to drive a two 7segments in single ic. I can I do it sir pls tell me

  • suhaib's picture
    suhaib
    Jan 03, 2017

    I built the circuit correctly but it not working , what is the problem tell to me

  • ask123's picture
    ask123
    Feb 04, 2017

    there is no wire connected to PIN13

  • thesecret2's picture
    thesecret2
    Feb 06, 2017

    i built the circuit correctly and check the circuit perfectly but it just display 0 when i press the count button it doesnt go up the reset button seems fine. please reply ASAP I really need help. you can help by taking pictures of what u built side by side and front please

  • nomanchrono123's picture
    nomanchrono123
    Feb 06, 2017

    can you make a list of a the connections pls so that we can understands well

  • ahmed's picture
    ahmed
    Feb 12, 2017

    I have connected the circuit and it works properly , thanks a lot for your help !!

  • Surru's picture
    Surru
    Mar 05, 2017

    I want to use 5 digits each with a 7 segment display. Do I need 5 of each of the components? I want a simple push button below each digit to increment from 0-9, no reset required. If I were to use an off the shelf assembled 5 digit display can I integrate just the push button to increament

  • lokesh sai's picture
    lokesh sai
    Mar 15, 2017

    sir i want to do 7 segment dispaly board to display my collage name ple can you help me how to do

  • biddi's picture
    biddi
    Mar 21, 2017

    my circuit works on Yenka simulation software, but does not work on breadboard. Seven segment is always showing 8 . Does not rest or count

  • Frank Stevens's picture
    Frank Stevens
    Apr 05, 2017

    Could you please send a picture of your Yenka circuit as I am trying to build something similar

  • James Myers's picture
    James Myers
    Apr 03, 2017

    I built the circuit as designed and of course it worked perfectly. I then tried to substitute a much larger display (2.24" character height) but it does not work. I assume that is because the original display (.56" with a Vf of 1.8) works well at 9VDC while the larger display has a Vf of 6.8, which will not function at 9VDC. Can you tell me what changes I need to make in the circuit diagram to enable use of the substitute larger display? Thank you for any help you can give me.

  • James Myers's picture
    James Myers
    Apr 06, 2017

    Thank you for the E-Mail response to my initial posting.  You asked about the 2.24" character height display that I tried to substitute after successfully building the basic circuit shown above.  This 2nd display is listed as Vf=6.8 @20mA and mcd=30@20mA (I don't know what mcd stands for and it could be critical).  The segment output color is Red.  Your note said "you could try this IC.... with a source current of 6.8mA".  If I understand you correctly, I should add current limiting resistors (10K) on each segment and increase Vdd to 15 VDC.  Does that also mean to continue using the IC4026.  P.S. I've recently found another 2.24" character height display with Vf=2.0 @20mA and mcd=34 @10mA.  Brilliant Red output color.  Thank you for your comments and I hope to hear from you on my latest post.

  • mahmoud abdelwahed 's picture
    mahmoud abdelwahed
    Apr 23, 2017

    plz I have built the circuit but the reset button didn't work what can I do
    thanks

  • mukesh azad 's picture
    mukesh azad
    Apr 23, 2017

    how can generate 1hz frequency for digital watch

  • adam ibrahim's picture
    adam ibrahim
    May 12, 2017

    please how will connect the circuit

  • Mário's picture
    Mário
    May 18, 2017

    tks great circuit!
    I like the CD4026 a lot, but what is the use for DEO - Display enable out?

  • Abhishek's picture
    Abhishek
    Apr 16, 2018

    Sir will this circuit work propely..... please reply sir'

  • JHB's picture
    JHB
    Jun 29, 2017

    It was such a lovely circuit. Couldn't get the common cathode display but had to create one with LEDs and it works perfectly when all components used conform with the exact specification, good one guys.

  • yza's picture
    yza
    Sep 17, 2017

    I cant make it work :( the schematic diagram btw. i have been trying i did exactly as it is in you schematic diagram but it really wont work :( please help

  • Nikita's picture
    Nikita
    Sep 21, 2017

    Do we need to program ic 555 here or use it as it is?

  • Catman847's picture
    Catman847
    Sep 30, 2017

    circuit is working correctly in simulation but I want to know how to replace button with sensor, my sensor is AD021 3-80cm proximity switch.

  • Catman847's picture
    Catman847
    Sep 30, 2017

    circuit is working correctly in simulation but I want to know how to replace button with sensor, my sensor is AD021 3-80cm proximity switch.

  • Phil Dee's picture
    Phil Dee
    Oct 25, 2017

    Can you show me how to put a switching the circuit to turn the display on and off to save battery power if left on?

  • Andrew Hodson's picture
    Andrew Hodson
    Oct 31, 2017

    Why aren't there resistors from 4026 to 7-segment? Can 1 get ready made PCBs of this circuit?

  • Panduleni's picture
    Panduleni
    Nov 07, 2017

    Can you please provide me with the purposes of the resistors, the capacitors and why of that values?

  • Ahmed Khalaf's picture
    Ahmed Khalaf
    Dec 09, 2017

    Hi,
    Can anyone help me here, am looking for a very simple BCD4026 manual electronic counter circuit that has a buzzer which will be ON when number of manual counts/clicks reaches 10, and the buzzer will stay ON until I hit a reset button. Please, any ideas or schematics around that can d that?

  • Ahmed Khalaf's picture
    Ahmed Khalaf
    Dec 12, 2017

    Hi,
    How can I modify your circuit by adding a Buzzer to make it beeping when you reach number 9 , and it will continue beeping until you click the reset button to stop the buzzer?

  • tousif's picture
    tousif
    Mar 01, 2018

    how can I operate 24v 7 segment diplay on same circuit?

  • AISHA's picture
    AISHA
    Mar 01, 2018

    There is no such thing as 24V 7-segment display. You can use any 7-segment display for this circuit 

  • Islam Salahat's picture
    Islam Salahat
    Mar 07, 2018

    I have an assignment that I should write a code for a 7 segment with 4 switches input
    explain >> 4 switches mean 4 bit X1 X2 X3 X4
    assuming X1=1 (switch on)
    X2=0 (switch off)
    X3=0 ( switch off)
    X4=1 (switch on)
    that mean input will be (1001) == (9) which mean the 7 segment will display 9
    and so on
    how can I write this code , (I am so bad at C++ programming and micro C programming )

  • Chris Justice's picture
    Chris Justice
    May 24, 2018

    The project is good and perfect.

    but I have a question....
    Apart from ic4026, Is their any other linear ic that is non volatile that is..ability to store last value of the 7 segment when power is of?

    with 4026, I must start counting from one any time I turn on, any linear ic that can store the last digit before turn of and display it automatically when turned on?

  • Rattan's picture
    Rattan
    May 31, 2018

    This circuit is working ok but I am facing one problem while cascading another ic after reaching digit 6 it jumps to digit 17 ,18 and count till 26 and again jump to 37 .I mean ic pin 5 generate pulse after 6 instead of 9. Please help me to solve this.thanks tkakur05799at the rate gmail.com

  • muid's picture
    muid
    Jun 06, 2018

    is it can count frequency of a circuit ?

  • Zhafran's picture
    Zhafran
    Jun 08, 2018

    Hello i want to ask something.
    Can i make this circuit using a PCB?

  • ajip's picture
    ajip
    Jul 25, 2018

    can u show me the circuit in PCB?

  • Dave Lennox's picture
    Dave Lennox
    Aug 02, 2019

    What would I have to do to have a self restart counter that counted from 0 to 9 then reset and automatically started counting again from 0 to 9, repeating this cycle continuosly.

    Thanx

     

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