Piezo beeper, voltage rating vs voltage range - Page 1
Forum section: electronics / beginners

author: Psi
author_rank: Super Contributor
timestamp: July 31, 2025, 03:08:49 am
content: You often see piezo beepers that have a voltage rating like 3V, 5V or 12V but also a max voltage range of 1-30V p2pDoes that mean it's safe to run the piezo at any voltage as long as your under 30V p2p, or do you have to stay at the voltage rating of 3V, 5V ,12V etc.I understand that the specs given like dB(A), current etc, are all given for operation at rated voltage, I'm more just trying to figure out what's safe to do without causing long term damage.Can I take a 3.3V rated piezo and drive it at +/- 12V (24V p2p) without damage if the datasheet says it's voltage range is up to 30V p2p?I'm assuming yes but am not really sure?

author: golden_labels
author_rank: Super Contributor
timestamp: July 31, 2025, 06:42:57 am
content: In this case the voltage rating is the voltage at which the buzzer is designed to operate at. Unless noted otherwise, all the specs assume you drive it at this voltage.You may see noteAN1176 from Diodes Incorporated, figure 4 on page 2. For this particular device they tested, beyond 5–6 V(P-P)the gains are marginal. But it safely operated at least to 16 V(P-P).But also confront this with the two charts on the next pages. One shows why you may wish to use higher voltage, when you’re away from the natural resonant frequency. The other shows what are the drawbacks.

author: RoGeorge
author_rank: Super Contributor
timestamp: July 31, 2025, 08:19:38 am
content: p2p means something else. For volts peak to peak, the notation is Vpp.

author: MariuszD
author_rank: Regular Contributor
timestamp: July 31, 2025, 09:01:46 am
content: QuoteThese are buzzers can have a built-in oscillator powered by DC.

author: Zero999
author_rank: Super Contributor
timestamp: July 31, 2025, 09:06:04 am
content: Are you talking about the type with a built-in oscillator or the bare piezo?If it has a built-in oscillator, then the semiconductors and capacitors are the limiting parts.If it's a bare piezo disc, then it probably will withstand higher voltages, than specified on the data sheet, but I doubt you'll gain anything in terms of sound pressure by running it at higher voltages and it will most likely shorten its life.Here's an oscillator I designed awhile ago. It uses bootstrapping to double the voltage, to get a square wave with a peak-to-peak voltage of quadruple the supply voltage, minus the losses in the output stages of the U1 & U2, the Schottky diodes and BJTs.If you want to run it at 5V, then U1 will need to be replaced with a 4000 series IC, such as the CD40106B, in which case it's a good idea to connect the gates in parallel to reduce the output impedance.Note my 74HC1G14 model probably isn't very accurate. I looked at the data sheet and put it together using voltage controlled switches and RC circuits to get the delays. I strongly recommend building it, rather than relying on the simulation.Bootstrap oscillator 2G.asc(3.21 kB - downloaded 4 times.)EDIT:Connecting U2 to the same power supply would save a resistor and enable the 74HC2G14, 74HC14 or a single CD40106B to be used. The only downside is the losses in Schottky diodes will be higher as more current flows through them.Bootstrap oscillator.asc(3.41 kB - downloaded 4 times.)