Simple 4026 Manual Digital Counter Circuit with Reset and Pause

In our normal practical life, we may face circumstances where we need a digital event counter in order to count certain events. Here I will give you some examples: people counter circuit in an auditorium, to count the number of products in a godown, to calculate an athlete’s performance and above all, all the digital clocks are basically counter circuits which generates an one second clock. Here we are providing similar kind of counter circuit diagram.

In this led 7 segment display counter circuit we are using a single digital counter IC (4026) both as counter and 7 segment driver. A common cathode 7 segment display is used here. The IC used here requires only clock pulses for operation.

By increasing the number of ICs and seven segment displays you can extend the counting limit up to infinity. This can also be made into a digital frequency counter circuit.

Some basic counters:

4026 Digital Counter Circuit Diagram

digital counter circuit

Components Required

  1. IC 4026
  2. 7 segment display
  3. Resistor 220 Ohm
  4. 6V power supply

Working of Digital Counter Circuit

  • IC 4026 is basically a decade counter (10 States – counts 0 through 9). Also it has an inbuilt 7 segment display driver which makes interfacing of 7 segment display easily.
  • 4026 drives only common cathode seven segment displays. As the name indicating a common cathode seven segment display has its cathode shorted and grounded.

digital counter circuit schematic

 

Animation of Digital Counter Circuit (If not animating click to open new tab)

  • Pin 1 is the Clock input and Pin 2 is the clock inhibit which is used for disabling the clock. It can be used to pause the counting when desired.
  • Pin 15 (Master reset pin) helps to reset the counter. Pin 2 and 15 are active high, so we are grounding them to enable the counting process. They should be connected to Vcc for their respective actions.
  • Pin 3 is display enable pin which enables the display.
  • Pin 5 is the carry output pin which generates a carry each time the count exceeds 9. It is used for extending the counting limit by connecting to the next IC’s clock pin.
  • For 2 digit display digital counter circuit 0 to 99 connect the carry out of the first IC as the clock of 2nd IC as seen below. You can increase the digits as much as you want by repeating the process with more ICs and displays.

0-99 7 segment display counter circuit

  • Resistor R1 is used as current limiting resistor. You can vary the brightness of the display by varying the resistance value. But this brightness will not uniform for each digit, Uniform brightness can be attained by connecting individual resistors for each anode segment.

Pin-out of 4026 Digital Counter IC and Display

4026 Digital Counter IC pinoutCommon Cathode 7 segment display

 

Next time we will be publishing a person counter circuit by using this principle.

56 thoughts on “Simple 4026 Manual Digital Counter Circuit with Reset and Pause

  1. Great design of the 0-99 counter! Thank you!
    Instead of using a 555 timer, I would like to use a momentary switch to trigger each pulse as a single event occurs. I am not sure which pins I would need to connect to the momentary switch.
    I know the clock pin (#1) is one of the pins but I need to where I should connect the other side of the momentary switch. (positive voltage or ground or another pin?).
    Also, I would like to know how to hookup the inhibit function (pause) switch and how to hookup the reset switch.

    Thank you so much for your time and for the circuit design!!!
    I would really appreciate the information!!!
    Have a great day!!!

    Merv Rosenquist

  2. Hi, After studying the 555 timer, it appears that the output from the 555 to the clock pin (#1) on the 4026 goes to Vdd to activate a pulse?

    Also, I plan on using a 100k 1/4 watt resister from Vss through an PNP switching transistor and a 22uf capacitor from the momentary switch to prevent switch bounce (false pulse counts), is that a good idea for this type of counter?

    The momentary switch is actually an electronic switch that uses a high speed NPN switching transistor so I’ll have to connect that to an input to the base of an PNP switching transistor (through a 100k resistor and a 22uf capacitor) to have an input a pulse from Vdd to the clock pin (instead of from Vss). The resistor is to limit current to the base of the transistor, the 22uf capacitor is to cause a delay in going to the off state to prevent false pulse counts. The electronic switch source is slow so to go to the off state so I want to add the capacitor. That circuit is activated by a thermistor so it takes about 35ms to go to the low state once it goes high. Does that make sense to you?

    Thank you for your time!
    MUCH APPRECIATED!!

    Merv Rosenquist

  3. I still think this circuit is one of the most straight forward, most reliable and most user friendly circuit out there. Thank you!!

    Merv Rosenquist

  4. Thanks for your useful explanations about this IC! Not even in Datasheets explains which is the function of the 2, 3, and 4 terminals! Only says “Display Enable input – Display enable output”, and nothing more! You clarified me very well the pin “2” purpose! Now I can understand that if I connect the pin “2” to +Vcc I could pause the counter, and if connect to ground, the counter will continue, is that correct?
    If I want to make a 2 digit display digital counter, the pin “4” must be connected to +Vcc? (Because it enables the output counter, that is, the pin 5) or just may be leave unconnected?
    Thanks so much!!!

    • Grigory Makeev,

      Yes, ALWAYS power the chip before adding inputs from other devices or it will reverse bias the delicate internal circuitry and damage the chip. This will insure that the internal circuitry is forward biased.
      That’s true with almost every IC chip. Some transistors and other similar individual devices can be reverse biased without damage but not in an IC chip 🙂

      Glad you got it working!! 🙂

  5. Achyut mathad,

    Resistors 1 and 2 go to the common cathode pins on the seven segment display (the negative pins). They are usually lettered rather than numbered (a,b,c,d,e,f,g are for the positive signal from the 4026 chip (better known as the Anode side on a Common Cathode Display), then DP is for the dot, some have CC written on them to denote the cathode or ground side, some have one CC pin on each side of the display so those will need to be connected together, then connected to ground through the one resistor.
    They make common Anode displays as well so make sure that the one you use is the “common cathode type”.

    Hope this helps to clear things up.

    • If I want to make a 2 digit display digital counter, the pin “4″ of the 1st IC must be connected to +Vcc? (Because it enables the output counter, that is, the pin 5) or just may be leave unconnected?
      Thanks so much!!!

  6. Alejandro,

    To add the second digit, leave pin 4 unconnected.
    Connect pin 5 (CO) from the first 4026 to the clock pin (pin 1) of the second 4026 chip.
    Everything else on the second 4026 including the display will be connected the same as the first one.

    Remember to place the second display in front of the display connected to the first 4026 chip since it only advances one digit for every ten digits coming from the first 4026 chip.

    Also, if you use a 555 timer chip for the clock and set it for 60 hertz using a resistor and capacitor to set the frequency, the displays will be fairly dim by using just one 100 Ohm resistor on the Cathode side.
    It will be brighter and more consistent if you use one 270 Ohm resister for each LED segment (seven 270 Ohm resistors coming from each 4026 chip, eight resistors “if” you use the dot. So, that’s one resistor for each lettered pin on the display), remember that is the anode side of the display and the positive output from the 4026 chip.
    Then connect the Common Cathode pins directly to ground with NO resistors.

    Hope this helps!

    • Also, Alejandro,

      Your are correct about “pausing” the counter by connecting pin 2 to Vcc, then reconnect to ground to resume counting.
      Also, you can “reset” the counter by doing the same to pin 15.

      Option one: You can use a single pole, double throw (SPDT) switch to accomplish both.
      Pause and Reset could be a two position toggle switch (One switch for each task). They will have three terminals on the back and have only two positions for the switch, (up or down).

      Option two for “Reset” You could also use a momentary (normally open SPDT) rocker switch for reset if you like.

      Have a great day!

      • how to reset this circuit using a switch? how to connect with pin 15. because whille disconnecting pin 15 from groung circuit reset.. should i NC contact. is dere any way to use NO contact

    • I tried resistors of various values on the cathode side of the 7-segment display. For all values, the segments seem to be of equal brightness. For example, with 220 ohms, the segments in the display of an “8” look to me to be the same brightness as the segments that show up in a “1”. And 500 ohms is dimmer, but uniformly on all segments. Are my eyes deceiving me? I wonder how this might work. I’m just learning some electronics, and all of this is new to me.

  7. Moshin,
    Connect a SPDT (single pole, double throw) switch between ground and positive, connect the center pin from the switch to pin #2 on the 4026 chip. When you flip the switch to feed it 5 volts or so, it will pause, when you flip the switch to feed pin #2 – 0 volts, it will start counting again if you’re using a 555 or similar timer to control the advancement of numbers on the display. If you only want it to count one number each time you flip the switch, don’t use the 555 timer.
    Look at the link above your poat that shows the switch setup. You can also use the momentary switch if you are only going to pause it for a second or two but you have hold the switch to keep it from counting.

    Hope this helps. If you need.further assistance, post a link to a picture of your setup and be sure to include exactly how you intent to use it and I can help you figure it out.

  8. I’m trying to play with this counter and i’m unable to find out the problem. In my case, if pin 15 (reset) is strictly grounded, the counter works. Otherwise this pin outputs (!) 5V voltage! If it is grounded, through this pin flows a significant current of 50mA, which is way too much in my opinion. Any resistor between this 15 pin and ground, as suggested everywhere, keeps high voltage on this pin and prevents IC from counting. I’m at a loss, since in every example I see, people send HIGH signal on pin 15 to reset it, but it _is_ already high in my case.

    • Found out the problem. I must have at some point connected the scheme wrong, – for example I knew nothing about the danger of supplying inputs before attaching Vdd. While replacing two chips I could have faulted them both :). Trying with the fresh one today with the same connections made it all work perfectly as expected.

      • Grigory Makeev,

        Yes, ALWAYS power the chip before adding inputs from other devices or it will reverse bias the delicate internal circuitry and damage the chip. This will insure that the internal circuitry is forward biased.
        That’s true with almost every IC chip. Some transistors and other similar individual devices can be reverse biased without damage but not in an IC chip 🙂

        Glad you got it working!! 🙂

        Oops, posted this reply further up in the thread. I forgot to hit reply to yours. 😀

  9. Hello … I’m double display (2 7segment setup) for our School Project in Logic …
    Didn’t use a 555 counter , only a spst switch with debouncer to count , 1 push = 1 count .

    My problem the 1st segment (tenths value) counts when the 2nd segment (ones value) goes from 3 to 4 instead of 9 to 0
    Any idea why? thanks

    • Hi shreyasbn,
      Of course, there is. The logic behind this idea is using RESET PIN (15). Design a digital logic circuit such that when a, b, c, d, f, g = 1, the output will be 1 and connect it in to pin 15. So that the counter will be reset itself for each 9 and start from the begging. :>

      -Jaseem

  10. the o/p of the 7 segment display coming in a occured way..all led r nor flash in an instant..it’s not coming in sequenceally…i am using a ir led tran & reciver and a comprator for the clk pulse of ic cd 4026be..help me out

  11. hi, am doing a heart beat monitor bt lacking the heart beat sensor device.What can I use to pick the pulses which are to be fed to two 555 monostable timers, then two 4026 and seven segment displays

  12. I did a logic display light using CD4017 @ d logic state I use 3CD 4017 and it count from 1 to 30 but am am a little bit confuse on this one the display is it only counting number or we can use it for words???

  13. Dear Sir
    I did the 4 digit counter using as shown the circuit above by cascade 5th to 1st pin clock its working fine but
    please kindly tell me how to reset the counter i request you pl give me the options

    Thanks
    Vinothram

    • 1st, Separate pin 15 and pin 2.
      2nd, Leave pin 2 and pin 15 connected to ground but separately.
      3rd, Briefly connect pin 15 (MR pin) to +6 volts, this will reset the counter, then connect pin 15 back to ground.
      This is best done with a momentary single pole double throw switch.

      To make the switch work properly, connect ground to the normally closed side of the switch, then connect +6 volts to the normally open side of the switch. Connect pin 15 to the center or common part of the switch.

      When you press or toggle the switch, pin 15 will be connected to +6 volts, then when released it will be reconnected to ground.

      Hope this helps

    • Hi Vinothram
      Connect Reset pins( PIN 15) of two cascaded ICs to VCC through a push button with a pull down resistor of 1K ohm to ground.

  14. HELLO EVERYONE!

    I’m in urgent need of help. Me and my team have chosen this particular experiment as our project. And we are beginners in electronics and hence don’t have a lot of knowledge about it. Thanks to your portal for helping us out. But I have some serious doubt about some things,

    1)We have with us the IC 555 timer as the input,and we’re building the multivibrator using it..we encountered a few terms such as DUTY CYCLE …what exactly is it?…so what values of components do I have to use (R1,R2 and capacitor) to make the counter count with time period of 1 sec.

    2) Coming to the main part…the resistor values mentioned are 220 ohms…will there be any difference if I use some other values which are close to it,such as 250 or 270 ohm?

    Hope my query is answered,
    Thank you!

  15. Hi there, I’m trying to build a counter circuit capable of counting items passing by. It needs to count up 5 digits, could you please send me some information which could help. I would appreciate it.
    Regards

  16. I’m building a counter with a slot sensor I have my 4026 ic working properly until I input my slot sensor then the counter acts as a stop watch when the slot signals 4026 any guidance please.

  17. is it necessary to use 555 Ic? because i made the same circuit using 4026 aand display but it gives fluctuating digits..randomly changing when clock pulse is not given (zero)

  18. is it okey to connect it with 555 timer and infrared signal to effect counting without the ripple blanking in terminal of 4033.. because i cant find 4033

  19. Yes you can connect 555 timer in monostable mode to 4026 all depends on what you want to use it for. Monostable if you want an object counter justake sure you have the right 555 chip. I couldn’t get my ne555 timer chip to work I forget what other 555 I used.

  20. please I was asked to design this digital event counter that can count to 1000 ie three digits. please how do I go about it

  21. Hello.

    Is it possible to make it sensor based ?

    I need full video with showing all of Equipment, Connections on Bread Board, Battery Connection.

    Kindly Help me. Please provide video or link which I’m in searching.

    Thank You.

  22. I want to use a momentary switch instead of the 555 monostable circuit..
    when i connect a connect a momentary switch to pin 2 , how much voltage i should give through the switch.

  23. how can i make a 4-bit up-counter (count returns to 0 after 15)with 7 segment display that allows user to choose automatic counting or manual counting.

    for automatic counting: count automatically when switched on
    for manual: count happens when controlled by a push button

  24. hello. i made this circuit with 3 7 segment led displays (999 counter)
    my problem is that i want to add a buzzer that sounds for 2 3 seconds when i reach 100. could you help me with that? i i think that i shoud use pin no 1 from the third 4026 as a trigger to a timer circuit in order to do that
    .thank you

  25. Hi, I need connect 4026(or 4033) output to IC 4073(logic “OR”) inputs. Can I do this connection without resistor here?

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