Piezo / buzzer without Arduino

I’m looking for a simple way to drive a Piezo/buzzer without the Arduino. I will trigger the piezo state (ON/OFF) from an Arduino digital pin but the square wave wont be generated by the Arduino. Is there a simple schematic out there for that ?

Thanks!

This can be the answer: http://www.electronic-circuits-diagrams.com/alarmsimages/5.gif

(search in G for "555 timer buzzer")

Thanks.
I found this helpfull infos : 555 and 556 Timer Circuits

Is there a way to hack the 555 to get a really nice beep sound from it. I tried many options, many piezos and i'm still not happy. I need a warmer beep sound. soft attack and release.

You may want to look at a speakjet;
http://www.robotshop.ca/magnevation-speakjet-ic.html

It has some built in sound effects, and if they aren’t what you need - you can make the arduino talk to you.

Otherwise, other FM Synthesis or self contained audio chips may do the job:
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=ISD4004-16MPY-ND

You can record what you want, and have the arduino play it back when you need.

(Look up ChipCorder(tm) too…)

Hey cool stuff there, i'm gonna need it for another project soon. But for now, i just need a simple beep sound but nice and warm, you know like the beep sound in your popular small electronic devices. I wish i could use one Arduino PWM pin and trigger/modulate the 555 ic and produce a variety of nice beep sound on purpose. :-/

Again, i can't use Arduino to produce the wave because he is already running other task and the wave sounds ugly that is why i need something external like the 555.

My problem is acoustic! I did put one of my many piezos in a small case with rubber around the piezo and it sound much better, warmer. ::)