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Does an MSP430 need any kind of circuitry to drive a "Self Drive" piezo


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I've got a self drive piezo that sounds loud enough at <= 3V and only uses <= 2mA. I know for an external drive piezo you should use a flyback diode and Transistor/FET to drive it, but wondering if either of these two are needed for the one I'm using.

 

Pretty sure there's no need at all for the transistor at such a low amperage, but not really sure if these self drive guys need the flyback for any kind of protection. Anyone have any experience?

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My understanding is the MSP430 pins should not be driven above 10mA. There are protection diodes in each pin (Vcc+0.7V and GND-0.7V I think) and they shouldn't have more than 2mA going through them.

 

Side note, the MSP430 F5172's VIO-driven pins can drive 20mA at VIO rail (1.8-5.5V) with two Drive Strength options per pin.

 

Sent from my Galaxy Note II with Tapatalk

 

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Yeah I'm sure the current/transistor side of things is fine, I was more worried about needing the flyback diode in case it behaved like an inductive load. But I've got to imagine that's handled within the drive circuitry itself or these would cause all sorts of problems.

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