If you've tried a 3.3 V device to a 5 V system, you know what a challenge it is. The bidirectional logic level shifter is a small device that safely reduces the 5V signal to 3.3V while boosting 3.3V to 5V. This level shifter is also suitable for 2.8V and 1.8V devices. The real difference between this logic level shifter and our previous version is that you can successfully set the high and low voltages and safely lift them on the same channel. Each level shifter has the ability to have 4 pins on the high side, 4 pins on the low side, with two inputs and two outputs for each side
The level shifter is very easy to use. The board must be powered by two voltage sources (high voltage and low voltage) used by the system. High voltage (eg 5V) to the "HV" pin, low voltage (eg 3.3V) to "LV", ground from system to "GND" pin