I am using this level shifter spark fun breakout board: https://learn.sparkfun.com/tutorials/using-the-logic-level-converter
My goal is to interface a 5V logic SPI LCD with a 3.3V logic micro controller. To start I have been testing the level shifter board to make sure I can get the correct levels. I apply 3.3 V from the micro controller to the TXI pin and get 5V on the TXO pin no problem. The issue is when I apply 0V to the TXI pin. This results in a 1.4V on the TXO pin. From the spark fun board schematic I see that it is using a MOSFET to apply the conversion and from my understanding when one side of the MOSFET is pulled low it enters into a conducting state and this should result in both sides going low. I don't understand why I'm seeing the 1.4V as opposed to just 0V.
If I'm stuck with the MOSFET going to 1.4 V for low-level logic should I expect my SPI LCD to treat 1.4 V as low-level logic and then operate correctly?