Soldered Qwiic I2C Long Range Extender LTC4331
A Qwiic board that carries I2C over an Ethernet cable to a second board, up to 30 m at 1 MHz or over 1200 m at lower speeds.
I2C was made for short connections on a single board, and a Qwiic cable that stretches much past a metre or two soon stops working. This board turns your I2C bus into a differential link carried by a standard Ethernet cable. Sensors and other I2C devices can then live in another room, at the far end of a greenhouse or across a building.
The link needs two boards, one at each end of the cable. The board next to your
microcontroller is the local side, which is the default. On the board at the far
end, connect the REMOTE pin to 3.3 V to make it the remote side. It then drives
the I2C devices attached to it. Your code stays the same: devices at the far end
answer at their usual addresses, as if they were on the same bus.
Solder jumpers select the link speed, from 1 MHz Fast-mode Plus over as much as
30 m of cable down to 100 kHz over 1200 m, and slower rates beyond that. The
headers also bring out the LTC4331's control and status pins: ON to switch it
into low-power mode, RDY and LINK to check that the link is up, ALERT to
pass interrupts back from the remote side, and CTRL to send one digital signal
to the far end.
This documentation is for
At a glance
What's in the box
| Qty | Item | Notes |
|---|---|---|
| 1 | Soldered Qwiic I2C Long Range Extender LTC4331 (main product) | 333415 |