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I'm trying to follow the examples in this CanJam EduKit project -- see page 2:

buzzer

I'm having enormous difficulty tracking down a piezo/buzzer that I could use for that project, a buzzer that:

  1. Works "natively" with the RPi and doesn't require resistors or support devices (capacitors, etc.); and
  2. Doesn't require too much power, doesn't draw too much current, etc.; and
  3. Activates/starts making sounds when I send a signal to it via GPIO output pin

I'd like to find a buzzer that I could wire up exactly like you see above that works with my RPi 1 Model A. I'd like to find that buzzer and order it ASAP! But that CanJam kit doesn't list any specs for the buzzer, and every buzzer I can find online so far is too powerful (requires too much voltage or draws too much current, etc.) for an RPi to handle without all sorts of special wiring + circuitry. I just want to wire it up exactly like above and fire off signals to it from a GPIO output pin!

Any ideas on what type of buzzer meets this criteria, and what trust-worthy sites sell it?! Thanks in advance!

  • Unlikely, the current limit is much too low. You should probably save yourself the headache and learn to use a transistor as a switch. GPIO are not meant to drive anything directly, they are control signals. Here is something to get you started – crasic Sep 22 '17 at 1:32
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    Adafruit has a 5V piezo that should fit the bill. adafruit.com/product/1536 – bobstro Sep 22 '17 at 6:50
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    In the "Learn" article linked to on the product page, they show it hooked directly between an Arduino (5V) pin and ground, but unfortunately, no more detail. I'm not sure of how much an Arduino Uno can put out. You might have to level shift or add some circuitry for the 5V. – bobstro Sep 22 '17 at 18:09
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    So for Arduino, the absolute maximum for any single IO pin is 40 mA. For the Raspberry Pi family, 16 mA be the maximum pulled from any 1 pin, and that 50 mA as the maximum from all pins. I wasn't aware there was that much of a difference. Sounds like we do need to find the specs for that actual part. Adafruit does have a very helpful online community. I've asked for details here: forums.adafruit.com/viewtopic.php?f=8&t=123965 – bobstro Sep 22 '17 at 20:22
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    @bobstro Why torture yourself with vendors that don't provide datasheets. Here is a suitable one without the guesswork - 3mA@3V digikey.com/short/qc1dt8 – crasic Sep 22 '17 at 20:39
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Strange that you have such a hard time finding one, I did use a search engine with "piezo 15mA" and the first two hits where 15mA/1.5volt piezo buzzers.

And a caution, your circuit can break your Raspberry, since the total power consumption can supersede the total for a Raspberry Pi.

The solution that makes sense is secure is a transistor and a couple of resistors, the way that you solve a circuit when having a MCU that isn't suited to drive a lot of loads!

Regarding the specified "Buzzers Transducer" with the electrical specification of Buzzers Transducer, Externally Driven Piezo 3V 3mA.

  1. Works "natively" with the RPi and doesn't require resistors or support devices (capacitors, etc.); and

Yes, ref to data Buzzers Transducer, Externally Driven Piezo 3V 3mA

  1. Doesn't require too much power, doesn't draw too much current, etc.; and

The current 3mA is well below the max current of 16mA that is the limit for a Raspberry Pi GPIO and the voltage of 3v as well.

  1. Activates/starts making sounds when I send a signal to it via GPIO output pin

Since the data is clearly within the parameters for Raspberry Pi the answer is still yes.

  • Thaks @MatsK (+1) - for the bounty, can you confirm that digikey.com/short/qc1dt8 meets the 3 criteria I posted in my original question? – smeeb Sep 25 '17 at 22:54
  • See last section of the answer that is changed to address that kind of buzzer. – MatsK Sep 26 '17 at 4:19
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Any 5V buzzer will do. I use one from a dismantled microwave oven in my desk alarm clock. Here’s a link to a good one: buzzer

It’s the exact same one I use. Pardon me, but those smaller buzzers you mention are cr?p. Microwave buzzers are always louder, cooler, and look sweet. When singularity is achieved, I’ll be sporting a gatling laser on one of my bionic limbs, and I’ll be using a microwave buzzer to alert raiders/others of their impending doom, when they jump the queue in the supermarket.

I CURRENTLY use one on an arduino with the toneAC library (which can be trivially made to work with wiringPi), but you don’t strictly need it. It will make it last longer, using a weak AC current.

Use a N-FET, like 2N7000 (S-G-D), or NPN like 2N2222A (E-B-C). For the 2N2222A, simply connect 5V in series with a 100 ohm resistor to a buzzer pin, the other buzzer pin to COLLECTOR of 2N2222A, and EMITTER to GND. Use a 1000 ohms resistor in series with a GPIO pin of your choosing, and on the other side of the resistor connect this signal line to BASE.

When you bring that pin HIGH, there will be a loud buzz. I had to use a 150 ohm resistor to make the buzzing less annoying. Enjoy!

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