I'm reading Make: AVR Programming. The next project wants me to try to drive an 8 ohm speaker with a pin from the microcontroller.
I'm no EE, but I do know that 8 ohms is not a lot of resistance, and it seems like we're going to run into problems running too much current through the microcontroller pin.
The book's solution is to use a "blocking capacitor". For some reason, I'm still a bit skeptical this is safe for my microcontroller. There are no resistors anywhere in sight. Here is the page from the book:
Question: if I don't care about sound quality, is this circuit safe for my microcontroller? The maximum current is supposed to be 40mA per pin.