I have a buzzer with an internal resistance of 16.5 Ohms, which I have used with an Arduino and it worked fine, so I assume it is 5V.
Can I connect a buzzer to the GPIO pins without a transistor, or would it damage the pins?
-
How could I know? I remember using that buzzer with an arduino and it worked fine, so I assume it is 5v.– EuphorbiumAug 8 '12 at 11:12
Add a comment
|
The maximum safe current from a GPIO pin is only 16mA
3.3v/16.5Ω would be ~200mA, so No. Definitely not safe
You would need to add a series resistor of 190Ω or more to make it safe to connect and then the voltage across the buzzer will be only 0.26V, so very very quiet
answered Aug 8 '12 at 11:30
-
-
Could @Euphorbium add a series resisitor? I don't know how buzzers work... Aug 8 '12 at 11:46
-
@AlexChamberlain, the buzzer would be very very quiet by the time the resistor was big enough Aug 8 '12 at 11:47