Piezo transducer extreme current

[Nicolaii]

Hi,
I am doing a project in which i need to power piezo transducer with 140 kHz ~20V signal. When I`m powering piezo with generator it only takes 6mA. But when I try to power piezo with my circuit it takes more than 1A. When i place resistor it gets hot and circuit lose power. Where is the problem?
Maybe you could give me advice of alternate ways to power piezo with such a signal?
**broken link removed**

 

[AnalogKid]

Is this your circuit?
How much current is available at the 20 V source?
What is the value of L1?
Do you know why L1 is in the circuit?
Manufacturer / part number for the transducer?

ak

 

[Nicolaii]

Current is up to 1.5A
Piezo is 14 nF and inductor 107 uH
L1 is here because of impedance stuff

 

[Tony Stewart]

Nicolaii get the RLC Nomograph and look up impedance at resonant f and ask yourself , does f match source and what is impedance of the switch and why does this lower Q in a shunt tank. Try a linear bias current sink sine wave at resonant f instead of a switched square wave and don't saturate L. Add plastic C if f is fixed.

 

[ronsimpson]

inductor 107 uH

What inductor? Part number? Picture?

Piezo is 14 nF

That helps but not much information.

 

[chemelec]

Why 140 KHz?
Will your piezo even operate at that Frequency?
And you also can't hear it.

 

[spec]

Hi,
I am doing a project in which i need to power piezo transducer with 140 kHz ~20V signal. When I`m powering piezo with generator it only takes 6mA. But when I try to power piezo with my circuit it takes more than 1A. When i place resistor it gets hot and circuit lose power. Where is the problem?
Maybe you could give me advice of alternate ways to power piezo with such a signal?
**broken link removed**

Hi Nicolii,

give the circuit below a try.

spec

 

[dr pepper]

Yes 140kc is very high.
Increasing the inductance of the inductor will reduce current flow and 'volume'.

 

[chemelec]

Which Piezo are you using?
Most Piezo's have a Limited Frequency range of reproduction.
Very FEW of them will do 140khz.