I think this has been said before but I can't find it, and a cursory review of the Freescale K20 datasheet doesn't turn up any physical device parameters (measured in Volts, Amps etc.).
What is the current source and sink capability of the Teensy 3 I/O pins? If I want to drive an optoisolator which needs 10 mA drive, is it correct to assume I will need an external driver to safely satisfy the current requirement?
What is the current source and sink capability of the Teensy 3 I/O pins? If I want to drive an optoisolator which needs 10 mA drive, is it correct to assume I will need an external driver to safely satisfy the current requirement?