TCAN1146-Q1: About the nINT and fault detection on TCAN1146.

Bruce,

Bruce Dai said:

        1. As fault detection requires the nINT configuration, both 12h and 29h registers need to be set, correct?

Yes, that is correct. Both bits should be set so that the SDO and nINT function are present, and then bus fault diagnostics must be mapped to the nINT pin. This will make it so that only bus fault interrupts will assert the nINT pin low. If left default as a global interrupt, the nINT pin will still assert low from a bus fault interrupt, but it will also assert low for any other interrupt.

Bruce Dai said:

         2.  If a fault interrupt occurs, and fault one hasn't been cleared yet, then fault two happens —

              The TCAN1146 will the 54h status be updated, or will it remain showing fault one?"

It will be updated and show both faults if the first was not cleared.

Bruce Dai said:

  3. In order to clear the nINT interrupt, is it necessary to clear the registers from 50h to 54h?

That is correct, all interrupts must be cleared, and the condition that caused the interrupt must also be gone. Otherwise, the interrupt will set itself again even after clearing.

Regards,

Eric Hackett