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Care should be taken though to ensure backwards compatibility to our old carrier boards or make sure new controller boards aren't used with any boards that use PB6/PB7 as GPIOs.
Add a Common Mode Choke for CAN
To reduce emissions on CAN and improve the EMC performance, a common mode choke + capacitor filters can be added. The downside of this is both the LC can create unwanted resonants, and during a fault on CAN (short to VBAT/GND), the inductance can create larger voltage spikes that can be damaging.
TI Claims that its automotive line of CAN transceivers can meet EMC requirements without a common mode choke, so they may be a viable option for MSXIV. One issue with the majority of AEC-Q CAN transceivers is that they require a 5V supply even if they're designed to work with 3V3 logic.
TI Application Note: Simplify CAN bus implementations with chokeless transceivers
Add Switchable Termination for CAN
Revision 7 of the Controller Boards introduced on-board termination using 2x 62R resistors and a capacitor. If wanted, we can potentially add a MOSFET or photorelay to create switchable termination resistors. The main use case will be during validation and testing, where the firmware can choose to have termination enabled or disabled in the configuration settings.
The downside of switchable termination will mostly be at the amount of board space needed and losing a GPIO pin that could've been used for carrier boards.
TI Reference Design: TIDA-01238: Controller Area Network (CAN) with Selectable Termination Reference Design