Current limits for teensy 3.5 pins, enough to drive a LED?

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Hafting

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Sorry if this is documented somewhere, I just could not find it.
What is the current limit for digital io pins on the teensy 3.5?
I plan on having a mux chip supplying power to a LED, with a resistor limiting the current to the 20mA the LED wants.

Can I drive the other end of the LED directly from a teensy 3.5 digital output? So that I if the teensy outputs "0" while the mux outputs "1", the LED lights up. The teensy will output 1 to turn off the LED and then there will be no current regardless of what the MUX does.
 
Don't have the data sheet handy but believe 20mA is in the 'probably works but outside the spec' region. Certainly wouldn't want to have too many at that level or you exceed the die total current limits.

edit:
25mA limit according to:
https://www.pjrc.com/teensy/K64P144M120SF5.pdf
So 20mA is fine as long as you don't have them all driving at that level, and you have done the math right.
 
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After 25 mA max it says: "Output high current total for all ports" is 100 mA { same 100 mA for LOW }

Also I think the default state is lower max current - to get 25 mA max current the port has to be set that way IIRC from seeing posts by Paul.
 
Always best to drive LEDs using 'digital' transistors with integrated base resistors. Search Digi-Key for 'digital transistor'. Some even have a diode in them for driving relays. This will help preserve your Teensy from accidental connections and overloads of the ports as Defragster has mentioned.
 
Thanks! I may need to drive 5 leds simultaneously. The mux has 16 lines, with 5 leds on each for a total of 80. (one led per key on a keyboard, using the same mux for scanning columns and also for driving leds.) 5*20 is 100, so perhaps I should go a bit lower to be on the safe side. 10-15mA will hopefully give enough backlight at 1/16 duty cycle.
 
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