Hey there,
I was making a password-based security system. The idea is simple, where there will be a preset password and a user password. If the password matches the green light will pop up and if it does not match the red will pop up. But it will have a security feature that will count the wrong attempts up to 3 times and after 3 wrong attempts counter will not increase and the buzzer will be activated.
I've completed the symmetric diagram in Proteus. But when I'm using 74HC48 IC to convert my Binary code to 7 segments display it's not working. I've tried many times but it's not working. I've watched many YouTube videos regarding this but they are using 74LS48 IC here to convert the binary to display. But I could not find the LS one in my country. Is there any problem with the voltage or anything else? Because I'm using a 9V battery here. Can anyone give me any idea how can I fix this? Or is there any other IC that I can use to solve the problem?
Here is my symmetric diagram. I'm also attaching the pdf version below for your convenience.

 

How have you connected pins 3, 4, and 5?
Connect them to Vcc. You cannot leave them not connected.

 

How have you connected pins 3, 4, and 5?
Connect them to Vcc. You cannot leave them not connected.

View attachment 291712

Yes, I've connected them in VCC in my breadboard circuit. But my 7 segment display not working.

 

Hi,
You should Not have 9v supply on standard 74xx devices.
E

 

Yes, I've connected them in VCC in my breadboard circuit. But my 7 segment display not working.

Can you elaborate on what you mean by "not working"?

 

You may have zapped some parts if you connected the circuit to 9V.
Suggest you look at the data sheet before you do a design next time.

 

Can you elaborate on what you mean by "not working"?

I meant by not working is, after completing the circuit connection the 7 segments display not glowing up. So I've checked every output pin of the IC with an external LED if it's giving high voltage but it's not working. So I think the problem is from IC.

 

You may have zapped some parts if you connected the circuit to 9V.
Suggest you look at the data sheet before you do a design next time.

I could not find the 74HC48 data sheet. But I got 74LS48

 

Hi,
You should Not have 9v supply on standard 74xx devices.
E
View attachment 291715

So can you give me an idea of how can I make a 9V battery to give me a 5V supply?

 

So can you give me an idea of how can I make a 9V battery to give me a 5V supply?

Use an LM7805 three-terminal linear voltage regulator.

 

I meant by not working is, after completing the circuit connection the 7 segments display not glowing up. So I've checked every output pin of the IC with an external LED if it's giving high voltage but it's not working. So I think the problem is from IC.

What happens when you connect LT, pin-3 of the 74xx48 IC to GND?
Is the LED on each segment working or blown?
Can you test each LED segment with a 1kΩ series resistor and your 9V battery?

 

So can you give me an idea of how can I make a 9V battery to give me a 5V supply?

Why not use three 1.5V cells, or four 1.5V cells and a diode?

 

By the way, when and if you do get it working, you don't need the external current limiting 220 ohm resistors in series with the LED's. They are built in to the 74LS/HC48!