TCAN4550: Schematic review

Denny,

Thanks for bringing this to E2E and that's great to hear we got a design in.

• Both power rails (VSUP and VIO) are correct configured, as well as VCCOUT and FLTR.
• I see WAKE is tied VBAT through a resistor. This is okay, but the local wake function won't be available, and I want to verify that's the intention.
• nINT needs an external pull-up unless the MCU pin nINT is connected to has an internal pull-up.
• What is the reason for a pull-up and pull-down on RST pin?
• GPIO1 and GPO2 are correct configured.
• The CAN bus components are correct with the common-mode choke, correctly valued termination, and filter capacitors. If the customer expects any voltage transients or ESD events, I would recommend a TVS diode on the CAN bus as well. A typical device we recommend is PESD1CAN.
• The crystal oscillator circuit looks correct, especially with the series resistors on both OSC1 and OSC2. What is the part number for the crystal?

Regards,

Eric Hackett

Dear Eric

Thanks for your feedback and suggestion, please check reply as follows and update schematic for attached file.

I see WAKE is tied VBAT through a resistor. This is okay, but the local wake function won't be available, and I want to verify that's the intention.

=> Yes, the WAKE function should be not used, but we will reserve this function from your remind.

nINT needs an external pull-up unless the MCU pin nINT is connected to has an internal pull-up.

=> OK, we had pull-up RES to SYS_3V3.

What is the reason for a pull-up and pull-down on RST pin?

=> Pull-up is just reserve, default is mount pull-down.

    (N.M) is not mount.

If the customer expects any voltage transients or ESD events, I would recommend a TVS diode on the CAN bus as well. A typical device we recommend is PESD1CAN.

=> Yes, We have already add TVS solution in schematic.

What is the part number for the crystal?

=> Please check attached file about XTAL SPEC.

E008B485-12D5-0344-E487-37C1E2F1FC05_333737.pdf

Many thanks

Denny