TCAN1044AV-Q1: TCAN1044AVDRBRQ1 Schematics check

Hi Kevin,

Thank you for the question. 

It looks like VCC = 5V supply and logic supply VIO = 3.3V which is good. Both have 0.1uF decoupling capacitors on the supply lines. In layout, please ensure that these capacitors are as close to the VCC and VIO pins as possible. 

The standby, TXD, and RXD pins from the schematic provided are ok. I don't see any of the connections past CAN_mode / CAN_TXD / CAN_RXD, so I can't comment any further on these pins. 

To make sure I am understanding the CAN bus correctly, the CAN_H and CAN_1 / CAN_L and CAN_2 wires are not connected purposely? The R154 and R155 are additional termination options that are not connected? If so, then this looks correct as split termination with R46 and R47 in series, paralleled to C44 which is 10nF. 10nF for the split capacitor is a good value, we generally recommend between 4.7nF and 100nF for the split capacitor. However, the split cap sizing all depends on your system and what corner frequency you would like for the CAN bus. 

I also see that C43 and C45 filter caps are present for additional filtering. These connections are good as well. 

Does the schematic include any external ESD protection / TVS diodes for the CAN bus, CMC, or series resistance options for additional protection to the chip? The ESD2CAN24  is an ESD protection device used to protect the CAN transceiver from electrically harmful ESD events. Series resistance also helps with electrical overstress EOS, and the CMC would also help to filter out any common mode noise on the system. These components are not required, but are recommended to ensure that the transceiver is protected fully. They are not needed for operation of the device U7. 

Regards,

Tyler