There is a very informative design guide written by Murata here http://www.murata.com/catalog/p15e6.pdf The easy way to get more volume out of a piezo=A0=A0 (if you just need a to= ne) without driving=A0 it harder is by driving it at the resonance frequency. (= or a harmonic of it) Peter van Hoof ----- Original Message ---- > From: Mark E. Skeels > To: Microcontroller discussion list - Public. > Sent: Tue, February 23, 2010 11:38:06 AM > Subject: [EE] piezo transducer failure mode on overvoltage. > = > List, I have an application using a audio piezo-transducer and it is = > rated at = 5V; we want to run it at 9V; because it is louder. I am = > wondering what the failure mode would be for a device like this. In the = > application, it runs for short duration (300 mS) and = infrequently. The = > average maximum cycle time is probably something = roughly like every 5 = > minutes (or more) when in use, but it can repeat as = frequently as ~1 second = > intervals as part of a "cycle." But each "cycle" = consists of only two = > beeps. I have run it at 9V as a test, but am trying to get a handle on = > what = could be expected longevity-wise at this elevated voltage. I = > have contacted the factory, but have received no response so far. I = > realize it's out of spec.=A0 =A0 :-) Is it power dissipation? Is it = > actual voltage? -- = Mark -- = http://www.piclist.com PIC/SX FAQ = > & list archive View/change your membership options = > at http://mailman.mit.edu/mailman/listinfo/piclist = -- = http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist