Hi TI partner:
We have a problem need your help.
We have a 1043 with nFAULT = L, RX = L, TX = H status. But it is not like the three problems described by datasheet (TXDDTO/TXDRXD/TSD).
CAN_H/CAN_L voltage drop to 1.25V (Because we connected two TCAN1043 in parallel, another one is OK).
RX impedance to ground is 140 ohm.
Does you ever seen this kind of problem?
Thank you a lot.
Best Regards
Bruce Hsin
Hi Bruce,
Based on your description, it sounds like the device has recognized a wake signal and is now in standby mode with the WAKERQ flag set. In this state, the driver is still disabled so the bus bias is not active, which is likely why you're seeing a recessive level lower than 2.5V. The WAKERQ flag which is causing nFAULT to be asserted will be cleared once the device transitions into normal mode (EN = STB = H).
Does this sound consistent with the observed behavior? Is it possible that activity on the CAN bus or WAKE pin caused a wake event to occur while the device was in sleep mode?
Regards,
Eric Schott
