No resistors are used to limit the current in keyboards?

[b1gtuna]

Hello everyone, I just designed a 35% keyboard PCB which uses Teensy 2.0 as the controller.
And I just realized there are no resistors used in the keyboards to limit the current flow between input and output pins.

Is this because the controller input has high impedance?

[Ray]

Is this because the controller input has high impedance?

Exactly

[b1gtuna]

Is this because the controller input has high impedance?

Exactly

gracias!

[flabbergast]

To have some numbers: atmega internal pull-ups should be about 50k.

[b1gtuna]

To have some numbers: atmega internal pull-ups should be about 50k.

Yup and I also checked that the maximum input/output current is 40mA. Thanks!