345876
Newbie level 2
Hello,
Sorry for the newb question. I am working on a fun little project that requires a greater current than an FTDI cable and USB port can provide. Therefore I need to use an external power supply. I can't just use a 3.3v FTDI cable because in some instances I will need to connect the project to an arduino like board that only outputs 5v.
I need the TX line from the FTDI cable to be brought down to 3.3v logic. I can do this with a 2.2K resistor in the TX line to the project, in parallel with a 4.3K resistor to ground.
But which ground do I use? Would connecting the two grounds solve the issue? I don't want to destroy my dc-dc voltage regulator for the external power supply. I have a feeling there is a bit more to it then that. Any help you can give is great, I am sure I also left out a key piece of info as well so don't feel bad letting me know!
Thanks!
Sorry for the newb question. I am working on a fun little project that requires a greater current than an FTDI cable and USB port can provide. Therefore I need to use an external power supply. I can't just use a 3.3v FTDI cable because in some instances I will need to connect the project to an arduino like board that only outputs 5v.
I need the TX line from the FTDI cable to be brought down to 3.3v logic. I can do this with a 2.2K resistor in the TX line to the project, in parallel with a 4.3K resistor to ground.
But which ground do I use? Would connecting the two grounds solve the issue? I don't want to destroy my dc-dc voltage regulator for the external power supply. I have a feeling there is a bit more to it then that. Any help you can give is great, I am sure I also left out a key piece of info as well so don't feel bad letting me know!
Thanks!