General • Pull Down Resistor Use

Hi all.
I am using a Raspberry Pi Pico for the first time. I have learnt that some GPIO pins default to high and some to low. I am planning to edit the config.txt file to make ALL GPIO pins to default to low at startup as all my inputs and outputs will only need to be high when activated (3.3Volts).

I read that I should (for reliability) also add pull down resistors to the GPIO inputs. A couple of questions:

1 - What value should I use? I read 10kOhm but I am worried about current drain as I am using lots of GPIO so each resistor adds to the current budget for the Pico.
2 - Some pins that default to low already have internal pull down resistors so should I just not bother adding a pull down resistor for these specific GPIO?
3 - For those GPIO that normally default to high I understand they have an internal pull up resistor, if I add a pull down resistor are the two fighting each other? Or when I edit the config.txt file to make all pins low at power up does the Pico switch out its internal pull up resistors.

Any guidance much appreciated thanks.

Statistics: Posted by MikeyStroud — Mon Jan 05, 2026 5:26 pm

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