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, 2012 at 11:12
Add a comment
|
1 Answer
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, 2012 at 11:30
-
-
Could @Euphorbium add a series resisitor? I don't know how buzzers work... Aug 8, 2012 at 11:46
-
@AlexChamberlain, the buzzer would be very very quiet by the time the resistor was big enough Aug 8, 2012 at 11:47