--- kravnus wolf <kravnus@yahoo.com> wrote:

> hi there,
> 
>     I am currently using a PIC to generate tones on
> the speaker. It runs on 5Volts. The speaker produce a
> tone which is too soft to hear after 5 meters away. Is
> it possible to increase the volume of the speaker
> using a 5Volts setup?
> 
> Thanks,
> John Chung

Yes you would want to use a bridge setup to drive the speaker. Driving
it with 5V gives you a 5Vpp signal or a 2.5V and a bit smaller RMS wise
in a bridge configuration you have 10Vpp which is a much larger signal
(and thus louder).   To do this however you need 2 PIC pins and 4
transistors in a full bridge setup. A less complicated variant is to
use a dual channel audio amp that can run off 5V and bridge the output.
 

Another way to increase volume is to use a lower impedance speaker. All
of these suggestions use more power so I recomend some careful
decoupling to prevent the noise being injected into the power supply.

Stephen R. Phillips was here
Please be advised what was said may be absolutely wrong, and hereby this disclaimer follows.  I reserve the right to be wrong and admit it in front of the entire world.


		
__________________________________ 
Yahoo! Mail - PC Magazine Editors' Choice 2005 
http://mail.yahoo.com
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist