4 Channel Level Shifter
The 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. 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 straightforward to use. The board needs to be powered from the two voltages 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.
These are 4 Channel devices (works great for I2C or SPI) and will work with all microcontrollers, Arduino, Raspberry Pi, Intel Edison, etc. Use this module to connect two devices of different digital voltage levels. For example: connecting an Arduino (5V device) to an ESP8266 (3.3V device).
The Level Converter comes complete with header pins and can be used directly on a breadboard.
https://www.pcboard.ca/4-channel-level-shifter