4 Channel (I2C or SPI) 3.3V-5V Bi-Directional Logic Level Converter If you've ever tried to connect a 3.3V device to a 5v system, you know what a challenge it can be. The bi-directional logic level converter is a small device that safely steps down 5v signals to 3.3V and steps up 3.3V to 5v at the same time. This level converter also works with 2.8V and 1.8V devices. What separates this logic level converter from our previous versions is that you can successfully set your high and low voltages and step up and down between them safely on the same channel. Each level converter has the capability of converting 4 pins on the high side to 4 pins on the low side with two inputs and two outputs provided for each side. The level converter is very easy to use. The board needs to be powered from the two voltage sources (high voltage and low voltage) that your system is using. High voltage (5v for example) to the 'hv' pin, low voltage (3.3V for example) to 'lv', and ground from the system to the 'gnd' pin logic level shifter bi-directional with 4 channels between high logic and low logic small module with 1.3Cm x 1.5Cm with 2 rows of 6 pin compatible with a breadboard, can be directly used in breadboard usage: for example, high voltage is 5v, low voltage is 3.3V hv connect with 5v power supply lv connect with 3.3V power supply and connect the power negative pole lvx input/output 3.3V TTL hvx input/output 5v ttl bi-directional transform between lvx and tvx