PCA9517 i2c translator a perfect companion for Raspberry Pi hardware add-ons

The rig pictured above works as an Internet connected temperature sensor which sends [Zaion] an email with a graph of the change over time. This in itself is interesting, but one part in particular caught our eye. He’s using an i2c temperature sensor , and we think the PCA9517┬áLevel-Translating I2C Bus Repeater that makes it possible is a perfect match for the RPi.

This is a Texas Instruments part. You can find more about it from the company’s product page. The key words in the name of the chip are ‘Level-Translating’. This has two bus connections, each with variable voltage levels. On side A the bus can be 0.9V to 5.5V. On side B the bus range is 2.7V to 5.5V. Since the Raspberry Pi I/O pins operate at 3.3V this could connect to the B side, give you the ability to interface with i2c parts rated for lower or higher voltages. This is especially handy for folks who started with the Arduino and own mostly 5V compliant prototyping hardware.

The part comes in a SOIC package, which you can easily hand solder and will costs around $1 depending on the supplier.