Because the Arduino & Raspberry Pi are 5V devices, and most modern sensors, displays, flash cards 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.
We do have some other handy level shifters in the shop, from the DIP 74LVC245 to the fancy bi-directional TXB0108. However, neither of these are happy to work with I2C,
ct the 3.3V device from 5V.
We do have some other handy level shifters in the shop, 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 BSS138 FETs with 10K pullups. 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
The Adafruit 4-Channel I2C Bi-Directional Logic Level Converter Features:
Level shifts to protect the 3.3V device from 5V
TXB0108 with an I2C-compatible FET Design
Has 4 BSS138 FETs with 10K pullups
Designed for use with I2C but works great for SPI, TTL Serial, and other Digital Interfaces - Both uni-directional and bi-directional
Fully assembled and tested PCB with 4 full bidirectional converter lines
Comes complete with 2 x 6-Pin Headers which can be soldered on for breadboarding
Downloads
Light Meter - Requiring Le
