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. Here we have used the popular 555 timer IC, CD4033 ICs and few other components, which are listed below.
Required 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
There are lot of online Tools
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.
Component Replacements
Is there any IC available that can replace 4033 and similarly for 7805?
You can use 4026 (Check this)
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.
Digital StopWatch
What will be the changes in circuit connections , , if I use common anode 7 segment display instead of common cathode ?
Then you need to use Common
Then you need to use Common anode 7 segment display driver IC like IC7446, instead of 4033.
the ic4033
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
yes, you can connect DE (not
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.
Yes, you can do that, just
Yes, you can do that, just connect the 555 in Monostable mode instead of Astable. Check this one: 7 segment counter circuit
Don't forget to ground the 14
Don't forget to ground the 14 pins on both the 4033s. It will work perfectly.
I've done that ..but still it
I've done that ..but still it's not working
How can i show the hidden
How can i show the hidden pins VDD/VSS in 4033 ??
VDD and VSS Pins are hidden
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
There are so many softwares
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
is there any equivalent ic
is there any equivalent ic for ic4033
Please read all the previous
Please read all the previous comments before asking questions, we might have answered them already.
hi sir is there any
hi sir is there any suggestion of new feature to add in this circuit?
i tried with both 4033 and
i tried with both 4033 and 4026 IC's but circuit don't run
@afrasiab @habib Try
@afrasiab @habib Try grounding the 14th pin of 4033.
i want pcb layout for these
i want pcb layout for these circuit .CAN u tell any online tool?
I want 4033 ic in protius
I want 4033 ic in protius with pin no 8,16
what changes i need to do if
what changes i need to do if i use IC 4026 insteed of IC 4033 please help me
Can you upload the proteus
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
The time is not changing on 7 segment
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.
what if I got common anode
what if I got common anode LED??
what IC should i use?? 4026 or 4033??
circuit doubt
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......
Juan Karlo if you want a
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.
IC information
What should i need to type to find ic 4033 in multisim. Is there any alternative ic instead of 4033?
Not working
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
telecommunication
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
it reset to 1 instead of 0
i build this but my reset button reset to 1 instead of 0 how to fix it
Can anyone tell me how can I
Can anyone tell me how can I get 10milisecond in stead of 1second?
Circuit is not working
I connect this circuit as given above but its not working.. means it just turn on the seven segment but never start counting....
Made the same circuit , but
Made the same circuit , but the seven segment never starts counting. What should I do?
circuit info
is there a step by step tutorial available for making this circuit please i need it very badly
about resistor
which resistor I will use in the replacement of 33k resister kindly guide
Thanks
digital stopwatch
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......
I want you helping me to
I want you helping me to connect this circuit on bread board with photos and steps
About working
I have tried this circuit more than 5 time. But I am not getting correct out put .
Debugging is very important
Debugging is very important skill to get any circuit to work.
What problem are you facing?
connect 14no. pin with 15no.
connect 14no. pin with 15no. pin of the 1st IC 4033
About the cathode seven segment
Is it ok to put a resistors in each pin of the seven segment so that the current will not direct flow in the segment?
do you have pcb layout for this circuit.?