This tiny Teensy add-on board features dual CAN-Bus transceiver circuits, including termination resistors. This enables the user to create a CAN-Bus MiM (Man in the Middle) or to bridge two CAN-Buses, for example. Typical power consumption is only 70mA (2x 35mA), which safely allows the board to be powered directly from the Teensy, while optional standby power consumption is as low as 16μA (2x 8μA). Dimensions are only 0.7" x 0.7" (17.8mm x 17.8mm), allowing for an unobtrusive design to easily access surrounding pins if needed.

An extra Rs pin for each transceiver enables switching to Normal mode (pull down to GND) or Shutdown/Silent mode (pull up to VCC) - see images on where to cut the trace for your choice of Shutdown capability, Silent capability, or neither.

Note: From 3/2024 these boards include jumper traces to disconnect either termination resistor. Simply cut the trace (see image). The CAN-H/CAN-l/GND pads have been changed from a 6 pad layout to 5 pads spaced 0.1" apart.

Note: From 10/2021 these boards feature Maxim MAX3051 transceivers and feature a green PCB mask color instead of red. These chips are identical, except Silent Mode is replaced with Standby Mode. Please read this additional info for the difference:
TCAN330's Silent Mode: This is the silent or receive only mode of the device. The CAN driver is disabled but the receiver is fully operational. CAN communication is unidirectional and only flows from the CAN bus through the receive path of the transceiver to the CAN protocol controller via the RXD output pin. The receiver is translating the differential signal from CANH and CANL to a digital output on RXD.
MAX3051's Standby Mode: If a logic-high is applied to RS, the MAX3051 enters a low-current standby mode. In this mode, the transmitter is switched off and the receiver is switched to a low-current/low-speed state. If dominant bits are detected, RXD switches to low level. The microcontroller should react to this condition by switching the transceiver back to normal operation.
This only applies if you choose to cut the right trace (see trace cutting diagram - option "Cut trace here for Silent mode"). If you choose to not cut either trace, the chip behaves the same.

The recommended and tested library for this board is the FlexCan T4 lib included with Teensyduino installation. More information can be found here https://github.com/tonton81/FlexCAN_T4.

Use cases: Car CAN-Bus communication (e.g. Engine bus and Entertainment bus simultaneously), communication between multiple Teensies, etc.