Hello Engineers. At places like small gatherings or meeting halls, small conferences, and classrooms it’s good to employ a visitor counter. This visitor counter circuit will count the visitor number of persons entered in the room or hall. The circuit explained in this tutorial today, is using two CD4026 ICs with two 7-segment LED displays. This Digital visitor counter circuit can go up to 99 counts. As soon as a person enters the room, the counter value increments by 1. So, let’s start with our topic Digital visitor counter circuit.
7- Segment LED Display
A 7-segment display module is an electronic device to display letters, digits, and numbers. These are the modules that are mostly used in devices such as electric meters, voltage stabilizers, test instruments, etc. Instead of the complex dot matrix displays, they are better and easier. They have separate seven segments that help to make a letter or number. 7 segment displays can have an LCD (Liquid Crystal Display) or LED (Light Emitting Diode) for each segment. A-F are markings for the individual components. They can be of 2 types. 1. Common Anode and 2.Common Cathode.
1.Common Anode – This means all anodes of each LED are common. To display a number or a letter we need to give ‘0’ or – ve to selective LEDs segment according to the code.
2.Common Cathode – All the cathode of each LED segment is taken as common and only ‘1’ is given to those LED’s anode that helps us to make our specific letter.
IC CD4026
IC CD4026 is a CMOS 4000 series 7-segment counter ICs and operates on very low power. This decade counter IC can count from 0-9 on a 7- segment common cathode display. We are going to use it in our visitor counter circuit today with the seven-segment display. Below are the circuit diagram as well as explanations and working.
PINOUTS
1. CLOCK PIN (CLK) – This is the pin number 1 which takes clock input. As soon as the clock pin goes high, counts are incremented.
2. Clock Inhibit(INH) – It’s the PIN number 2 and it should be low ( ground) to enable the clock pin pulses.
3. Enable Pin( DEI) – This is PIN 3, it should be kept high(+5V – 9V) so as to enable the output pins A to G.
4. DEO pin – PIN number 4 it’s always high(+5V – 9V) in case if we more than 1 CD 4026 IC.
5. CO pin – PIN number 5, used for cascading: i.e carry forwarding the counting by using another IC.
6. PIN 7 to 13 – These are all output PINs that provide decoded output.
7. VSS pin 8 – Ground.
8. PIN 14( UCS)- Unused. Only used rarely for the division.
9. MR – PIN number 15. Memory reset or resetting the counter to start from 0.
10. VDD or VCC – This PIN powers the IC. (5V – 9V).
Circuit Diagram for digital visitor counter
Materials
- R1 – 10K-12K ohms – 1pcs
- R3 – 47K to 50K -1pc
- R2, R4 100ohms – 2pcs
- IC CD4026 – 2pcs
- 7-segment display common cathode (buy 5 Pieces @ $ 2.64 i.e Rs 200 INR)- 2pcs
- Also check Buy 7 segment display common cathode for Rs.11 per pcs cheap, can buy in bulk also
- LDR 1M – 1pc
- 9V Battery
- 16 pin DIP connector( for ic base on PCB) – 2pcs
- PCB
Working for Digital Visitor Counter
As shown in the circuit above, there are two 4026 decade counter ICs first one having a primary clock input and the second one having cascaded to the previous stage. Also, there are 2 common cathode LED displays, one with each IC.
The Laser light is continuously striking the LDR unless or until someone doesn’t cross by through it. So, as we know with the intensity of light the LDR resistance is very low. This makes the base connected to the ground and shorted by the emitter. When someone crosses between the path of the laser, the light is absent for a second and resistance of LDR is very high(1M). This makes the base to get adequate supply and transistor is ON. This makes IC get clock pulse input via CLK pin and the counter is incremented with output displayed on the LED display. After that same thing goes on and on till 9.
IC 1 PIN number 5 ( CO) output goes to PIN 1 of IC2 as the clock pulse input. It is for carry forwarding of bit that goes to another counter. Once the previous counter counts up to 9 and resets to 0, the carry-out pulse is forwarded to the 2nd decade counter.
Display 1 shows the digit 1 and displays with IC2 shows digit 0, it starts with 10 now. This same process of carry-out goes on and on between IC s. Common PINs of both displays are connected to ground as its common cathode. Max. count by this counter can go is the largest 2 digit number 99.
So, guys, I hope you liked it. Let me know in the comments section about any queries or doubts. Thanks. Subscribe to our newsletter for the latest post updates.
what are the practical application of visitor counter, like can it be implemented in shopping mall , theater and can this system be merged with other software to make it more advanced? And CD4026 ic count up to only 99 i mean 2 digit…like what if have more than 1000 visitors will this be useful..what kind of changes we need to do in this. and you have used LDR light dependent resistor in this circuit. for for night time its okay it will excite the circuit to get enough resistance when light stops falling on it. BUT what about day time when light will continuously fall on it? another question you have not mentioned any diac, triac or silicon controlled rectifier to excite the circuit when the resistance is very high when light stops falling on LDR..
THANKS
Hello Rishi, Thanks for visiting.
Answering your questions…
1. practical applications, I have already given in article itself.
2. This is just a typical IC based system If you want something like software-based then u have to use a microcontroller or raspberry pi for more advancement. But I don’t think it’s needed.
3. IC CD4026 can also go above that value 99 too It can go even up to 3 digits easily just we need to employ one more IC4026 Counter and one more 7 segments common cathode display. But just in this circuit, it’s going up to 99max cause we haven’t employed any extra IC and display.
4.LDR will only detect the laser light which is falling in a straight line over it, there is no role of day-night cause LDR will be employed in such insulation that surrounding lights can’t affect it. It’s obvious. AND NO DIAC NO TRIAC NOTHING!.
Please refer to my other older articles for the basic understandings about LDR and all stuff.
Thanks for visiting.
Thanks for your reply abishek/
Thank you for taking the time to write and post this material.
Best regards,
Demir Raahauge
When I originally commented I clicked the “Notify me when new comments are added” checkbox and
now each time a comment is added I get four emails
with the same comment. Is there any way you can remove
people from that service? Thanks!
Hi, I am sorry for your hassle but there is no option on my site like what you told you clicked. None of the other visiter is facing this. In cases, if the problem persists you can contact me through the contact form.
Great job
Thankyou sir
Nice article man
Thanks for visiting.
Greetings! Very helpful advice in this particular post! It’s the little
changes that produce the largest changes. Thanks for sharing!
entrancing
cool
why did u use specific ic
Hello Sonia, thanks for visiting. I have used IC4026 to drive the 7segment display. IC 4026 Provides the decoded output to display the digits on the 7 segments led display in an incremental sequential way each time a pulse is received at its clock pin.
Using this IC makes the circuit small and easy to show the digits count on the Display.
thank
I good article
nicw
Pretty! This has been a really wonderful article.
Many thanks for providing these details.
VERy nice broo
Thanks for visiting bro
Good post. I was facing many of these issues as well..
Cool..I want to read even more things about it!
Oh my goodness. Impressive article dude.
Many thanks to you, a very relevant note.
Wow, this post is nice, my sister is analyzing these kinds of things, thus
I am going to convey her.
nice its working
Good idea
Great post.
hi sir, i am Rabin from Malaysia i am electric guy i like to do electronics project for accumulate knowledge i like ur project and i done it i have some idea can we share the project is count in figure with sensor support in same time how can i count the figure out from the room in same display. exp. in the room counter show there is 90 in room after 30 minute 15 person from when out wash room so my display must show me the figure 75 in room it is for safety purposes also let say in this time the room get fire the display show me 90 but inside 75 only how soft it got any pin to count down in the ic
Hello electroinvention.co.in webmaster, Your posts are always insightful and valuable.
Thank You so much
A visitor counter is a great tool to use in smaller settings, such as small gatherings or meeting halls, small conferences, and classrooms. It can help you keep track of the number of people in your space and ensure that you don’t exceed the maximum occupancy.