Often we need stopwatch to differentiate the time of two events. Here in this tutorial we are going to design a simple digital stopwatch circuit, without using any microcontroller.
Components
- IC 4033 - 2
- 555 timer IC -1
- Common Cathode 7 Segment Display -2
- 150 Ohm -1
- 100K resistor -1
- 33K resistor -1
- 56K resistor -1
- 10uF capacitor -1
- On/off switch -1
- Push button -1
- Bread board -1
- 9 Volt Battery -1
- Battery Connector -1
- LED -1
- Voltage Regulator 7805 -1
- Connecting wires
IC CD4033
This is counter and seven segment decoding in one package IC which is very easy to interface with seven segment displays. This is fully static counter operational IC and ideal for low power displays. This IC can be used for decade counting seven segment decimal displays, frequency division seven segment decimal displays, clocks, watches, timers, counter/display driver for meter applications.
Digital Stopwatch Circuit Diagram and Explanation
In this circuit we have used a 555 timer IC based astable multi-vibrator which is for creating 1 second delay. And two common cathode seven segment decoder IC’s namely CD4033. The output of astable multivibrator is directly applied to seven segment decoder IC’s (U4) Clock pin (1) and carry output pin(5) of U4 IC is directly connected to clock pin (1) of second seven segment decoder(U3). And two seven segment are connected with these decoder (U3 and U4). Its connections are shown in stopwatch circuit diagram given below. One push button is used to stop /start the stopwatch and one push button is used to reset the stopwatch. A 5 volt voltage regulator is used for providing 5 volt to whole circuit. And a 9 volt battery is used for powering the circuit. Rest of connections are shown in the circuit diagram.
Working
In this stop watch circuit we have generated one second delay by using 555 timer based astable multivibrator. By using some calculation we can easily generates one second delay. In astable multivibrator there is two resisters and one capacitor is responsible for delay by charging or discharging capacitor through resistors. Calculation formula for generating delay for astable multivibrator is given below.
F=1/T= 1.44/(R1 + 2R2) C1
In this project we have selects R1 is 33K, R2 is 56K and C1 is 10uF. [Also check: 1 minute timer circuit]
Ass Astable multi-vibrator generates one seconds delay, this delay is oscillations or pulse of 0 and 1. So we will use this pulse for triggering the seven segment decoder then seven segment decoder changes the digit number with the one second of time period.
When we ON the stopwatch (by start/stop button) it start counting from zero and if we turned OFF the same button then counting is stop or pause until again turned ON the same button or press reset button.
There are two seven segments, so this stopwatch circuit can count 00-99 seconds time.
Comments
Sep 20, 2015
do you have pcb layout for this circuit.?
Oct 06, 2015
There are lot of online Tools and softwares available, which convert schematic into PCB layout like Fritzing, you can design a good PCB layout using those.
Nov 01, 2015
Is there any IC available that can replace 4033 and similarly for 7805?
Nov 03, 2015
You can use 4026 (Check this) in place of 4033. And you can remove 7805 and connect 9v battery directly, otherwise there are lot of voltage regulators available.
Dec 12, 2015
What will be the changes in circuit connections , , if I use common anode 7 segment display instead of common cathode ?
Dec 17, 2015
Then you need to use Common anode 7 segment display driver IC like IC7446, instead of 4033.
Feb 03, 2016
if i am to use the 4026 instead of 4033.. instead of connecting to rbi, i connect to DEI? thats all that changes? pliz help
Feb 08, 2016
yes, you can connect DE (not DEI) to Vcc like RBI, which is connected to HIGH in 4033. Leave DEO open in 4026 like RBO in 4033.
Feb 16, 2016
Can this circuit me modified to count manually with each push of the switch.
Feb 23, 2016
Yes, you can do that, just connect the 555 in Monostable mode instead of Astable. Check this one: 7 segment counter circuit
Mar 16, 2016
Don't forget to ground the 14 pins on both the 4033s. It will work perfectly.
May 05, 2018
I've done that ..but still it's not working
Apr 21, 2016
Hi,
I am trying to extend this circuit to an activity tracker and save it to an SD card. Can this circuit be modified for that?
Apr 28, 2016
Hi,
Can anyone tell me how to make the second 7 segment display count only till 5?!
thank you.
May 04, 2016
Hi.
My output stuck at 68 its not working please help!
May 27, 2016
How can i show the hidden pins VDD/VSS in 4033 ??
Jun 04, 2016
How can i show the hidden pins VDD/VSS in 4033 ?? my project error if VDD And VSS gone :D
Jun 11, 2016
VDD and VSS Pins are hidden and by default connected to 5v power rail and Ground. Further check by Right click, Edit Properties and click on Hidden Pins of the component. This link may be helpfull: http://electronics.stackexchange.com/questions/148893/connecting-the-vdd-terminal-in-proteus
Sep 01, 2016
I want PCB layout for this ckt diagram
Oct 01, 2016
There are so many softwares are available for Schematic to PCB layout conversion like Easy EDA, Fritzing etc. We have made tutorial for using Easy EDA for PCB conversion Design Your Circuits Online for Free with EasyEDA
Sep 01, 2016
I want to be ckt diagram plz send
Oct 16, 2016
is there any equivalent ic for ic4033
Oct 27, 2016
Please read all the previous comments before asking questions, we might have answered them already.
Oct 17, 2016
hi sir is there any suggestion of new feature to add in this circuit?
Nov 16, 2016
i tried with both 4033 and 4026 IC's but circuit don't run
Dec 01, 2016
which resistor you used in both common point of 7 segment cathode display . you didn,t mention that .pls help may be reason to work my circuit . otherwise everything right ..
Mar 04, 2017
@afrasiab @habib Try grounding the 14th pin of 4033.
Mar 01, 2017
Has anyone produced an working pcb design?
Mar 11, 2017
If i use common anode seven segment decoder here then what i have to do? please,help me
Mar 12, 2017
i want pcb layout for these circuit .CAN u tell any online tool?
Apr 17, 2017
I want 4033 ic in protius with pin no 8,16
May 27, 2017
I real like this site
Jul 31, 2017
what changes i need to do if i use IC 4026 insteed of IC 4033 please help me
Oct 06, 2017
Can you upload the proteus project file? I am not able to unhide VSS and VDD pins i tried following the tutorial you posted earlier in comment section
Oct 06, 2017
Sir, i connected tye circuit as shown in circuit but all the lcds on 7 segment glow at same time making "8" and keep on blinking.
Oct 11, 2017
what if I got common anode LED??
what IC should i use?? 4026 or 4033??
Oct 23, 2017
Hello
i am having a doubt regarding the your connections....
if we connect according to the circuit diagram, what you have given in the site....
is it working????
i have connected according to it but i am unable to get the output.......
i have checked it trice....
please help me in that regard....please......
Nov 30, 2017
how can i set it at a countdown from 10-0?
Dec 02, 2017
Juan Karlo if you want a countdown circuit then you should create it by your self using combination of D flip flops and decoder. the flip flops will start like the circuit above from 0 to 9 i.e a counter circuit the change will you make will be in the decoder who will display 9 for 0, 8 for 1 and so on. That is it will decode in opposite manner to the circuit above.
Dec 08, 2017
What should i need to type to find ic 4033 in multisim. Is there any alternative ic instead of 4033?
Jan 06, 2018
sir all the connection are perfect but circuit is not working.. Common cathode seven segment is remain on 0 0... i have try it many time but still not working
Feb 24, 2018
hi can you make a video full clearly of digital stopwatch to me i have doubt in video that's why i can't understand how element connected with each other
Mar 11, 2018
i build this but my reset button reset to 1 instead of 0 how to fix it
Mar 29, 2018
What is D2?
Jul 10, 2018
LED
Apr 06, 2018
Can anyone tell me how can I get 10milisecond in stead of 1second?
Apr 17, 2018
can it be resumed after stopping
May 02, 2018
I connect this circuit as given above but its not working.. means it just turn on the seven segment but never start counting....
May 05, 2018
Made the same circuit , but the seven segment never starts counting. What should I do?
Jun 03, 2018
is there a step by step tutorial available for making this circuit please i need it very badly
Jul 10, 2018
which resistor I will use in the replacement of 33k resister kindly guide
Thanks
Jul 27, 2018
Hello
i am having a doubt regarding the your connections....
if we connect according to the circuit diagram, what you have given in the site....
is it working????
i have connected according to it but i am unable to get the output.......
i have checked it trice....
please help me in that regard....please......
Aug 02, 2018
I want you helping me to connect this circuit on bread board with photos and steps
Aug 27, 2018
I have tried this circuit more than 5 time. But I am not getting correct out put .
Aug 29, 2018
Debugging is very important skill to get any circuit to work.
What problem are you facing?
Sep 03, 2018
connect 14no. pin with 15no. pin of the 1st IC 4033
Sep 03, 2018
In the first 4033 IC, connect the 15pin with 14pin........if the problem is not solved then connect 14pin of each 4033 ic to ground
N.B - make sure your reset button is connected perfectly...!