Can't find part number for piezo beeper

#1

My piezo beeper is broken and I want to replace it. Is there a list of parts for the main board? I have equipment and experience with surface mount repair so I am confident I can replace it. Is there a project in github that would have the BOM? I looked but can’t find it. Thanks

#2

Hi Ntech,

I am afraid there is no list of parts for our main board.
You may try if you can get one by other way.

#3

I suspect one of these (link) might work.

#4

It’s disappointing that a project for children that is supposed to be ‘Open Source’ is more closed source and keeps their design secret.

#5

Thanks for the reply. I know you’re probably thinking that my question is dumb or lazy but that’s not the case. Let me try to explain.

I have learned a lot about piezo buzzers this last week. Some appear electrically as a pure 20 nF capacitor and have to be driven with a circuit that includes a discharge path for the ‘capacitor’. Others appear electrically as a 15 Ohm resistor and must be driven with a ‘push-pull’ driver. Some drivers need to limit the current. Yet others just need power applied and they emit a tone. The list continues with combinations of capacitance, inductance and resistance and functionality.

My point is that searching ebay for piezo buzzers yields a list of 400 buzzers of all types. Literally none of the sellers understand how to specify the buzzers and so it’s impossible to find one that would work without buying a bunch of them and trying them.

The fact that the manufacturer refuses to provide a parts list tells me a lot about their goals. I will not be recommending this product for our schools for that reason. The maker of mBot has told me ‘you may try if you can get one by other way[sic]’.

Thank you again, I do appreciate the suggestions.

#6

Nah, I don’t think it’s laziness, just a starting point. :wink:

Have you looked at the schematic (link)? It shows a 2.2K resistor in series with the buzzer. Still doesn’t help identify the exact part, but may help with inferring what the values need to be. Perhaps a better question to @tec_support might be to ask for the specs on the buzzer rather than a part number because they likely buy them from different manufacturers for different lots. Just a thought.

#7

I’m pretty much on the same path as you suggest.
I’ve looked at the schematic & actually breadboarded the circuit to test some of the buzzers I have on hand. R22 is a 51 Ohm resistor which is needed to drive an electro-magnetic buzzer. As opposed to a piezo-electric buzzer which has a different driver circuit.
I have searched everywhere to find this device which is 9mm in diameter and 5mm high with pin spacing of 5mm. Some of the China websites hint at parts close to this but not in small quantity.
I have contacted tech support and have been rebuffed with basically ‘good luck’.
I’m just going to brute force one of the buzzers that sort of works and leave it at that.
Thanks for your help & suggestions.

#8

This might be the one (link) although the minimum order would run somewhere between $27.00-$50.00 USD plus shipping. Here’s one at Amazon (link) that would run you under $8 USD.

Good luck!

Chuck

#9

Hi ntech,

The specification of beeper on mCore is Passive electromagnetic buzzer
Straight 9mm * 5mm (diameter * height) 5V

#10

Thank you for your reply, but it does not contain useful information.

With a metric ruler, I have already measured it, so the dimensions are obvious to the most casual observer.
I have also measured the pin spacing which you have left out.

It is obviously electromagnetic by looking at the drive circuit (15 Ohms and kickback diode).

By specifying 5V you are just stating the obvious, ie that the mbot drives it with 5V. But these devices are specified as a range (ie 3-30V), not at a single operating voltage.

What would be helpful is the manufacturer and part number, but apparently that is Top Secret.

#11