EYE ON NPI - Analog Devices' LT3960 I2C to CAN-physical transceiver #EYEonNPI @DigiKey @Adafruit

The LT3960 is a high-speed transceiver which creates the functional equivalent of a single-master I2C bus in the CAN physical layer and is powered from a single wide-ranging input voltage. Using two integrated CAN transceivers, the LT3960 creates a differential proxy for each of the single-ended I2C clock and data signals which is capable of traversing harsh or noisy environments across two twisted pairs.

Please note! The LT3960 is not a I2C to CAN bus converter/adapter. It isn't like your CAN devices will appear on an I2C bus or vice versa. It's just a physical-layer converter: basically it lets you use your existing I2C controllers and peripherals but without the restrictive single-ended transmission layer:

It should be noted that while the LT3960 uses the CAN physical layer to conduct bidirectional I2C data, the CANSCL and CANSDA buses created by the LT3960 are not traditional CAN buses carrying traditional CAN data. As such, the CANSCL and CANSDA buses between LT3960 devices cannot be shared with standard CAN transceivers in a multidrop configuration.

However, you can (ha!) have multiple I2C sensors on the end of the long cable, either by having multiple sensors connected to one LT3960 or multiple LT3960's tied to the I2CAN bus along the route. A nice touch is the separate VIN pin, connected to a high-voltage LDO that can drop 60V down to 3.3V so you could also pass a high voltage power signal down the cable that could be then regulated at the end, locally, to provide power to the transceiver and sensor.

So whether you're using an Arduino UNO, STM32F405 or Raspberry Pi main controller or data logger, you can take advantage of the existing I2C controller you've already got. Then use this low cost chip on either side of your sensor network to create a durable network without the added complexity of having I2C-to-CAN nodes.

[rpavlik]

Cool, an I2C extender using differential signaling 😁 Neat! I also like the Stemma QT to micro grabber cable, a nice little sister to the alligator clip one. I don't remember seeing that in the store, I'll have to go looking!

[ghwizz]

Yet another great eye on NPI and such a neat device! Shame they are still using the old names for the controller and peripherals, seeing them nowadays seems jarring, like when you see an old movie where everyone is smoking!

[arvidjedlicka]

How long before a small board with two RJ45 connectors, one on each end (allows the Cat5 to be daisy-chained easily), the LT3960, an LDO and a STEMMA QT connector on the side is available????

[CathyInBlue]

So, to be clear, the CANBus segment that these units form is only for the passing of I²C messages. It's not possible to use this to give a µC with I²C an bridge into an existing CANBus network that has native CAN devices talking on it. Is that correct?

[ParallelLogic]

Sounds awfully similar to the LTC4311 breakout

[oleksandrgrytsenko]

Can it be replaced with two common CAN drivers (eg TJA1050) for each of I2C lines?
With connected together CANTX, CANRX and pulled-up I2C line (SCL or SDA).