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Electrical Engineering/Understanding a circuit diagram

Question

piezo buzzer circuit
QUESTION: Hi Cleggsan,
How are you? I hope you are genki.
I am interested in running an external drive piezo buzzer off a PIC microcontroller and I am trying to understand what components would be needed in the circuit. I have found this circuit diagram for a piezo buzzer but I am not sure if I have understood it correctly - are the square waves being supplied by a microcontroller here? Am I correct in thinking that in addition to the microcontroller and the piezo buzzer, the circuit requires a transistor, two resistors, and a diode?

I "think" I have understood, but I do not want to proceed under any false assumptions!

Domo arigato
Eddie

Buzzer data sheet if you are interested -
http://www.microbuzzer.com/buzzer/spec/TE-HPS12C-H2.5.pdf

ANSWER: Yes, you are again and as usual correct in your analysis.  You are just unsure of your own confidence!

There are two resistors, diode and transistor connected as shown in the schematic diagram.  The buzzer is a really loud one!

But, you must supply an input signal. It can come from any sine wave or square wave or pulse type generator circuit.  And, yes, there are hosts of ICs that will produce such signals to drive the buzzer circuit.

Ok.  You are headed the right direction.  Best wishes.  Ohaiogozaimashita\\

---------- FOLLOW-UP ----------

QUESTION: Thanks Cleggsan,
I am now trying to determine the microcontroller that suits my requirements and I am not sure what features I need or do not need.
I need to do two things - one is to supply an input signal to the buzzer, and the other is to control a sleep/wake cycle for an RF receiver. In order to perform these tasks, I am assuming that I need a timer and an oscillator at the bare minimum, am I understanding that correctly?
In order to minimize the power consumption of the receiver, I have been looking at XLP microcontrollers (for example- http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en539800) Can I still use an XLP controller if one of the controller's tasks is not a low power one? Do I need to use two separate microcontrollers in this case, or can an XLP controller also be used for another, non-XLP application?

Arigatogozaimasu!
Eddie

The http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en539800 is a computer chip. It is overkill for driving a piezo buzzer.  It is certainly a very low power processor that is optimum for portable and small devices where battery power must be conserved.  But it is a full computer chip that requires software programming. Its internal clock is running at 8MHz so it is not a super fast computer like you would find in a pc but fast for ordinary functions.  It is capable of 16 MIPS which makes it a good little computer.  And so on.

I don't understand the relation between the buzzer application and the rf receiver. Is there a connection? Or are they two separate projects?

Further enlightenment needed.

Hasta La Vista

Electrical Engineering

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cleggsan

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All technical areas of Electronics Engineering.

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BSEE, MBA, Design, R&D, University Research.
Senior Life Member of IEEE. Life Fellow of AES.

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IEEE, Consumer Electronics Society, Audio Engineering Society.
Broad teaching experience; work experience mostly in consumer electronics and conversion from analog to digital technologies. Pioneer in digital audio at all levels.

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BSEE (Equiv) BYU BSEE University of North Dakota MSBA (MBA) Illinois State University Graduate Studies in Computer Science - Bradley University Graduate Studies - Ohio University Graduate Studies - University of Missouri Kansas City DeVry Tech - Electronics