8 simple electronic doorbell circuit by 555 timer IC

schematic diagram of electronic doorbell circuit
Simple electronic doorbell circuit (monostable 555  timer IC)

This project  is  a simple electronic doorbell circuit powered by a battery source ranging from 6 volts to 12 volts. This doorbell circuit is powered by a 555 timer IC operated in monostable mode. The use of the timer IC is to set the time delay for the doorbell to ring. The 100K resistor and 33uF capacitor sets the time delay about 3.6 seconds of continuous ringing. Increasing the value of resistor and capacitor increases the time delay about the product of resistor-capacitor combination times 1.1 (1.1RC).
The switch S1 is a push button that will activate the electronic doorbell. The 10K resistor across the S1 and supply voltage provides protection of false triggering of 555 timer.
The buzzer to be used must be self oscillated type or having a built in oscillator for this doorbell circuit to function well.
For  persons with some problem in hearing, you can modify the door bell circuit by replacing the buzzer to LED and 150 ohm resistor (see diagram below), or you can put this LED and resistor in parallel to buzzer for better functionality
The LED is preferably blinker type, but an ordinary one is just okay.
schematic diagram of simple electronic doorbell circuit for deaf
Simple electronic doorbell circuit (astable 555  timer IC)

Another version of simple electronic doorbell is shown bellow. This type of electronic doorbell uses the same 555 timer IC but it is operated in astable operation a generating an audible sound of 2880 Hz. Another difference of this doorbell circuit is the buzzer is replaced by a speaker. The sound frequency is set by the resistors 1K, and 2K, and 100nF capacitor. Increasing their value lowers the pitch of the doorbell sound.

The same with the electronic doorbell above, you can replace the speaker with an LED as an indicator. Advantage of this type of electronic doorbell is you can use a buzzer or speaker while the version above can’t. Disadvantage of this version is it requires more parts and you are going to push the button (S1) all the time for the doorbell to sound.
another version of doorbell


  1. How many volts for the buzzer? Can we use a speaker as a replace for the buzzer?

  2. Bryan good day!
    Buzzer is 6V if your supply is 6V and 12V buzzer for 12v supply.
    We have 3 versions of doorbell circuit, the first is using a buzzer and the last one is using speaker.You can use only a speaker using the last circuit above.. Replacing speaker instead of buzzer may cause the circuit not to work..

  3. hi'
    what if the person(deaf) is sleeping?

  4. what if the person(deaf) is sleeping?
    I cant think any idea how to answer that or how this circuit will help. Be honest with you, this circuit cant help you if that is the case.

  5. >what if the person(deaf) is sleeping?

    You can touch a tesla-circuit, then connect the output of the teslacoil (ca. 10.000 volts) directly to a aluminium-foil, witch is placesed near the sleeping person!
    I'm 100% sure, the sleeping person will wake up imediatlly...or never again:-)

  6. >what if the person (deaf) is sleeping?
    That's the funniest i've ever heard. that's absolutely true

  7. >what if the person (deaf) is sleeping?

    You can connect this circuit to a bucket of water that will simply flip off and poor the water on the person's (deaf) face. this way he will know that someone is calling for him.


  8. The Liztek wireless doorbell features a wide range extending to 1000 feet in an open area and 500 feet in an enclosed area. So, you will never miss any visitors even if you are several rooms away.