Because the Arduino (and Basic Stamp) are 5V devices, and most modern sensors, displays, flashcards, and modes are 3.3V-only, many makers find that they need to perform level shifting/conversion to protect the 3.3V device from 5V.
There are some other handy level shifters available in the market, from the DIP 74LVC245 to the fancy bi-directional TXB0108. However, neither of these are happy to work with I2C, which uses a funky pull-up system to transfer data back and forth. This level shifter board combines the ease-of-use of the bi-directional TXB0108 with an I2C-compatible FET design following NXP’s app note.
This breakout has 4 2N7002 FETs with 10K pull-ups. It works down to 1.8V on the low side, and up to 10V on the high side. The 10K’s do make the interface a little more sluggish than using a TXB0108 or 74LVC245 so we suggest checking those out if you need high-speed transfer.
While we designed it for use with I2C, this works as well for TTL Serial, slow <2MHz SPI, and any other digital interface both unidirectional and bidirectional. Comes with a fully assembled, and tested PCB with 4 full bidirectional converter lines as well as 2 pieces of 6-pin header you can solder on to plug into a breadboard or perfboard.
Features and Specifications
- Number of Channels 4
- Voltage on Lv Side 1.8V-5V
- Voltage on Hv Side 2.8V-6V
- Power 2.8V – 6V
- Length (mm) 16
- Width (mm) 13
- Height (mm) 3
- Weight (gm) 2
- 1 x I2C Logic Level Converter 4 Channel