Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

an amplifier for buzzer

Status
Not open for further replies.

Fahime

New Member
Hi,
What's a good amplifier for Piezo buzzer.
I want to have 50Vp-p on the buzzer so it's very luad.
Please help.
 
Hi,
What's a good amplifier for Piezo buzzer.
I want to have 50Vp-p on the buzzer so it's very luad.
Please help.

Whats the type of piezo, can it handle 50Vppk.???
 
I have 20Vp-p on Piezo now. But it's not as luad as I need. What can I do to have it
lauder

The easy way would be a 1:2.5 step up transformer, a small audio transformer with the correct ratio would be ok.

You say 20Vppk, how is the 20V drive being generated.?
 
It depends on the power available, and what the sounder takes - they are series resonant, and can take considerable power.

As Eric says, how is it generated?, it 'may' be simple to make it bridged and approach 80v p-p quite simply.
 
I think I'm not using the right buzzer in the operating frequency. I have to change the buzzer and then I don't think as big as 20V amplification is required. 10V may be ok. what do you think?
 
I think I'm not using the right buzzer in the operating frequency. I have to change the buzzer and then I don't think as big as 20V amplification is required. 10V may be ok. what do you think?

hi,
What sound intensity do you want in dB at what frequency.????

What will be the piezo sounder driving circuit.??
 
I need 85 dB at 400Hz to 1100Hz.
I'm using a trasnistor to drive it.

A 12V driver will be sufficient to produce 85dB.

Use a 555 operating at the resosnant frequency of the piezo transducer.

Look at these two pdf's for reference.
 

Attachments

  • 102542.pdf
    111 KB · Views: 629
  • 66700.pdf
    157.8 KB · Views: 402
Last edited:
A piezo transducer is a high frequency whistle. It won't produce much sound at only 400Hz to 1100Hz.

A single transistor can't drive a piezo transducer. The driver must be push-pull.

Sound pressure must be stated at a certain distance. The distance for 85db might be only 10cm. At 20cm the sound pressure is only 79dB. At 40cm it is only 73dB. At an arm-reach distance the sound pressure is only 67dB.
 
I piezo transducer is a capacitor that has no resistance so a single transistor can pull it only in one direction but not drive it with AC.
 
I piezo transducer is a capacitor that has no resistance so a single transistor can pull it only in one direction but not drive it with AC.
What happens if we have a resistor in parallel? Can' it discharge the capacitor of the Buzzer?
 
Because a piezo is capacitive it needs to be discharged. You could connect a resistor in parallel with it to discharge it but it would limit the efficiency to <50% and wouldn't be very loud.
 
A piezo transducer does not produce a good mid-frequency analog sound because it ihas sharp high frequency resonances. The main resonance is somewhere between 3kHz to 5kHz so nearly any lower frequency will produce harmonics in that range and they will be very loud.
I think the resonances make it sound very distorted.
 
Piezo transducers are only useful for producing simple tones e.g. alarms, musical greetings cards, sound effects in children's toys etc.

I would never consider using one in any application where you need semi-decent sound quality.
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top