EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: quaternion00 on April 15, 2020, 01:46:27 am
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Hi folks,
I was driving a piezo transducer with 6V(peak-peak), 2 kHz using a function generator. I saw on the oscilloscope that the waveform did
not looked like a square wave. I know that a piezo transducer is like a capacitor. I thought that the distorted waveform was
due to fast charging and discharging of the piezo transducer. So I tried to put a 1k resistor in parallel with the piezo and the waveform did not changed (still distorted). I tried decreasing and increasing the value of voltage and parallel resistor but the waveform did not changed .
In my knowledge, the sound is louder when the piezo waveform is close to square wave. what are the ways to make the piezo waveform close to square wave so it will have louder sound? Attached is the piezo waveform I captured.
Thanks :)
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You can add some small resistance in series (instead of in parallel). It will lower the Q of oscillating (resonating) cirquit.
Amplifiers usually don't like capacitance strait on their output so you have to separate it a little.
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the sound is louder when the piezo waveform is close to square wave
Where from did you got this info, or why do you think it should be like that?
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a square wave spends more of its time away from 0 volts than a sinewave does.
if you crank up the gain on a sine wave to the point where its too loud for whatever ya playing it through it will clip or peak. this means the sine has gone so big its head and toes are cut off and you just get a square wave. music CDs that have been mastered by shit head audio mastering engineers are all cranked up so they are louder, but unfortunately it buggers the wave form and ya get crappy sound.
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"I was driving a piezo transducer with 6V(peak-peak), 2 kHz using a function generator."
Are you sure it is a piezo, the waveform looks much closer to driving a 16 ohm speaker. :-//