The Logic Level Converter Module provides a bidirectional interface between devices operating at different voltages. The typical application is use of 3.3V sensors or devices with a 5V microcontroller such as an Arduino. Up to 4 digital I/O lines can be converted.
LO V: Connect to the power supply voltage for the low-voltage side.
HI V: Connect to the power supply voltage for the high-voltage side.
Low V I/O 1-4: Connect to digital I/O lines on the low-voltage side.
High V I/O 1-4: Connect to digital I/O lines on the high-voltage side.
GND: Connect to GND (0V) on both the low-voltage and high-voltage sides.
The GND connections on both sides of the Logic Level Converter Module are connected internally to tie the GND reference voltages together on both sides of your circuit. Make sure the low and high voltage portions share the same GND reference or this module won't work!
Connect the low and high voltage references to the supply rails for your circuit. These could be 2.2V, 2.8V, 3.3V, 5V - it really doesn't matter. Although the most common application for this module is linking 3.3V and 5V parts, it could just as easily be used to link 2.2V and 2.8V parts, or 2.8V and 5V. As long as you connect the low and high voltages on the correct sides, it will work.
The logic channels are bidirectional, and four are provided. It doesn't matter if you don't use all the channels, and a typical application could be linking serial TX and RX lines in which case only two channels will be used. Simply leave the other channels unconnected.