Maker Pro
Maker Pro

piezo and uP

Hi all!

Could someone tell me how to make a piezo louder?
I did connect it directly to uP PIN and to ground, only 5V is avail in
circuit.
also I woundn`t like to use externel ICs such MAX232 to imprve voltage
over piezo.
I have got square wave with piezo`s resonate freq.


any ideas?

besr regards
david
 
P

Pooh Bear

Jan 1, 1970
0
Hi all!

Could someone tell me how to make a piezo louder?
I did connect it directly to uP PIN and to ground, only 5V is avail in
circuit.
also I woundn`t like to use externel ICs such MAX232 to imprve voltage
over piezo.
I have got square wave with piezo`s resonate freq.

any ideas?

Drive one pin with the uP and connect the other pin to an inverted version of
the same signal. I hope you have a spare inverter handy. It'll double the volts.

Graham
 
S

Spehro Pefhany

Jan 1, 1970
0
Hi all!

Could someone tell me how to make a piezo louder?
I did connect it directly to uP PIN and to ground, only 5V is avail in
circuit.
also I woundn`t like to use externel ICs such MAX232 to imprve voltage
over piezo.
I have got square wave with piezo`s resonate freq.


any ideas?

besr regards
david

Homework problem?



Best regards,
Spehro Pefhany
 
M

martin griffith

Jan 1, 1970
0
On 26 May 2006 04:33:14 -0700, in sci.electronics.design
Hi all!

Could someone tell me how to make a piezo louder?
I did connect it directly to uP PIN and to ground, only 5V is avail in
circuit.
also I woundn`t like to use externel ICs such MAX232 to imprve voltage
over piezo.
I have got square wave with piezo`s resonate freq.


any ideas?

besr regards
david
Put a small tube on it, it will "amplify it". Adjust the length of
the tube for maximum sound


martin
 
i have got tube, i do alsa connect it with NPN key and the inductor
across the piezo but it is still not lout enough any more ideas ?
 
S

Spehro Pefhany

Jan 1, 1970
0
Put a small tube on it, it will "amplify it". Adjust the length of
the tube for maximum sound


martin

Or design a tuned (eg. Helmholtz) cavity.


Best regards,
Spehro Pefhany
 
Q

Quack

Jan 1, 1970
0
connect the uP PIN to a transistor to switch the power (5v) through the
piezo.

The uP PIN is probably only capable of driving a few Ma.

Alex.
 
S

Spehro Pefhany

Jan 1, 1970
0
it is capaple to rive bout 20ma, itis connected via transistir...but
still not loud enough...

Drive a push-pull step-up transformer with, oh, 100mA or 200mA, then.


Best regards,
Spehro Pefhany
 
S

Sjouke Burry

Jan 1, 1970
0
Hi all!

Could someone tell me how to make a piezo louder?
I did connect it directly to uP PIN and to ground, only 5V is avail in
circuit.
also I woundn`t like to use externel ICs such MAX232 to imprve voltage
over piezo.
I have got square wave with piezo`s resonate freq.


any ideas?

besr regards
david
Connect it to two inverted outputs,it doubles
the voltage.
 
P

Pooh Bear

Jan 1, 1970
0
martin said:
On 26 May 2006 04:33:14 -0700, in sci.electronics.design

Put a small tube on it, it will "amplify it". Adjust the length of
the tube for maximum sound

12AX7 ? ;-)

Graham
 
P

Pooh Bear

Jan 1, 1970
0
Sjouke said:
Connect it to two inverted outputs,it doubles
the voltage.

I think you mean connect it to the output and an inverted output ! ;-)

Graham
 
K

Ken Smith

Jan 1, 1970
0
Hi all!

Could someone tell me how to make a piezo louder?
I did connect it directly to uP PIN and to ground, only 5V is avail in
circuit.
also I woundn`t like to use externel ICs such MAX232 to imprve voltage
over piezo.
I have got square wave with piezo`s resonate freq.


any ideas?


Try using a different piezo. The quality varies a fair bit from brand to
brand. In general the larger ones are louder.

Place the device as it will be in the final product and hook a generator
up to it and find the loudest point. This may be far from the makers
published resonant frequency number, depending on the mounting.

Drive the device with a discordant sound. They always sound louder and
get more attention.
 
S

Slavek

Jan 1, 1970
0
Connect parallel piezo with inductor. Calculate inductance for
resonanse at the maximum laoudnes of piezo. Use driver with overvoltage
and other protections.
 
D

Dirk Bruere

Jan 1, 1970
0
martin said:
On 26 May 2006 04:33:14 -0700, in sci.electronics.design

Put a small tube on it, it will "amplify it". Adjust the length of
the tube for maximum sound

Called a "Helmholz resonator"

Dirk
 
Top