I plan on using a bluetooth module to communicate with my phone, and send data to an arduino. I am going to use an HM-11 module, which is a 3.3v module. I understand that the supply voltage will be 3.3v, as supposed to the 5v the arduino runs on. However, will the arduino be able to read the signals from the bluetooth module, as it is a 3.3v one? Or do I need to use a level shifter to make the 3.3v 5v before it is input into the arduino?
tinkerkid:
However, will the arduino be able to read the signals from the bluetooth module, as it is a 3.3v one?
Yes
I believe you need to level-shift the 5v Tx signal from the Arduino.
However you don't need to level-shift the 3.3v Tx signal from the Bluetooth device.
...R