Hey yall!
I just now realized the Teensy 4.0 is only supposed to handle 3.3 volts....
I did something probably dumb and made a pcb that takes a bunch of normally open push buttons, pull them to 5V through a 10k resistor and go into the teensy. I also used the INPUT_PULLUP in the software.
when i measure the voltage at the teensy input it is like 3.9 volts!! soo. maybe i'm not totally screwed ? Is it possible that the internal pullup of about 33k tp 3.3V and my external pull up of 10k to 5v are making a kind of voltage divider and I am in the clear? or do i need to kludge some wires and change that 5v to a 3.3v..?
i layed the PCB out in the worst way so changing the 5v going to all the resistors is going to be a real pain. everything actually works fine, but this is going in a permanent installation and I won't be there to monitor it and fix things when it goes away from me in a few days.
heres my schematic so you can see clearly what I'm doing. all the labels are going to different pins of the teensy.
THANK YOU for any guidance! i just realized this might be bad and it has to leave my shop in a few days!
I just now realized the Teensy 4.0 is only supposed to handle 3.3 volts....
I did something probably dumb and made a pcb that takes a bunch of normally open push buttons, pull them to 5V through a 10k resistor and go into the teensy. I also used the INPUT_PULLUP in the software.
when i measure the voltage at the teensy input it is like 3.9 volts!! soo. maybe i'm not totally screwed ? Is it possible that the internal pullup of about 33k tp 3.3V and my external pull up of 10k to 5v are making a kind of voltage divider and I am in the clear? or do i need to kludge some wires and change that 5v to a 3.3v..?
i layed the PCB out in the worst way so changing the 5v going to all the resistors is going to be a real pain. everything actually works fine, but this is going in a permanent installation and I won't be there to monitor it and fix things when it goes away from me in a few days.
heres my schematic so you can see clearly what I'm doing. all the labels are going to different pins of the teensy.
THANK YOU for any guidance! i just realized this might be bad and it has to leave my shop in a few days!