hello everyone I need help
I damaged accidentally a very loud piezo and I need to rebuild it
The piezo was driven from mcu pin connected to a npn ztx614 transistor and a kind of a transformer (I’ve attached pics of it) witch I broke
Can you help me find this part or something similar so i can take again this loudness I had?
It’s use was like amplifier I think
Thank you !

 

hello everyone I need help
I damaged accidentally a very loud piezo and I need to rebuild it
The piezo was driven from mcu pin connected to a npn ztx614 transistor and a kind of a transformer (I’ve attached pics of it) witch I broke
Can you help me find this part or something similar so i can take again this loudness I had?
It’s use was like amplifier I think
Thank you !

Yup that's a transformer. It's function is to transform the signal up or down in voltage and current, to match up the output of the MCU and transistor, to whatever the piezo needs. It loses a bit of power in the transformation but gives a for better result than directly connecting the two with some sort of mismatch.

Two questions: How do you know, or how sure are you that this is the broken part? Do you have any information you can share like model numbers? Finding the right transformer will depend on the details of the MCU, the power supply and the piezo.

 

Yup that's a transformer. It's function is to transform the signal up or down in voltage and current, to match up the output of the MCU and transistor, to whatever the piezo needs. It loses a bit of power in the transformation but gives a for better result than directly connecting the two with some sort of mismatch.

Two questions: How do you know, or how sure are you that this is the broken part? Do you have any information you can share like model numbers? Finding the right transformer will depend on the details of the MCU, the power supply and the piezo.

I have put one more pic witch saws the schematic off the connection with this part
Yes I’m sure because in my effort to disassemble the buzzer with this I completely brake it
The mcu is a pic 16f88 and the buzzer was a murata but this unfortunately is all I know

 

You can repair the transformer, remove the tape carefully and unwind the broken wires and re_solder them.

Otherwise look for audio output transformer, select the one with a ratio of about 15:1 or higher like LT700 Blue.

https://www.ebay.co.uk/itm/Eagle-LT...6ef:m:mkNFldjiZ70mYeMhSCKGTZw&redirect=mobile

 

You can repair the transformer, remove the tape carefully and unwind the broken wires and re_solder them.

Otherwise look for audio output transformer, select the one with a ratio of about 15:1 or higher like LT700 Blue.

https://www.ebay.co.uk/itm/Eagle-LT...6ef:m:mkNFldjiZ70mYeMhSCKGTZw&redirect=mobile

What you mean by 15:1 ratio? Sorry but I’m completely new to transformers the one on picture what ratio has for example ?

Thank you!

 

The bigger the Turns ratio, the higher the output voltage will be.

That picture maybe a 5:1 ratio, so if your pic is pulsing out 5V, then a 5:1 transformer will give out 25V approx .

 

The bigger the Turns ratio, the higher the output voltage will be.

That picture maybe a 5:1 ratio.

And I have to search only in audio transformers correct?
I’m looking at farnell but I can’t find audio transformer with so big ratio

 

Your circuit uses 9V so a 5:1 transformer will give out 45V, that should be ok.

 

Your circuit uses 9V so a 5:1 transformer will give out 45V, that should be ok.

So for replacing this I have to also check if the Vmax for the piezo is 45v and less ? And also if the ratio is 3,6:1+1 what does this means??

Thank you and sorry for stupid questions

 

Transformer ratio means>> for every Volt you put in you get more out.

So a ratio of 3:1 means 1volt in gives 3volts out,.and vice versa..

Yes check the Voltage limits of your piezo., it's probably 25_30V