Alternative Buzzer signal generation for Piezo speakers?
Posted: Mon Jul 16, 2012 1:02 pm
As far as I understand it, the current buzzer code simply changes the buzzer pin from low to high and it's up to the buzzer hardware to actually convert this into an audible signal. Wouldn't it also be possible to have the flight controller generate a PWM signal on that pin that could be used to drive a small piezo speaker? It probably requires a dedicated amplifier circuit (a transistor or something like TI's LM4960 driver chip), but it would have some benefits:
References:
http://hades.mech.northwestern.edu/inde ... with_a_PIC
http://tronixstuff.wordpress.com/2010/0 ... -thirteen/
http://www.picbasic.co.uk/forum/showthread.php?t=3076
http://www.electronicspoint.com/driving ... 39264.html
- No magnetic interference
- Much lower power consumption than traditional beepers
- Multiple beep frequencies possible
References:
http://hades.mech.northwestern.edu/inde ... with_a_PIC
http://tronixstuff.wordpress.com/2010/0 ... -thirteen/
http://www.picbasic.co.uk/forum/showthread.php?t=3076
http://www.electronicspoint.com/driving ... 39264.html