ZHCSN78E january 2021 – march 2023 TCAN1043A-Q1
PRODUCTION DATA
The following device status indicator flags are implemented to allow for the MCU to determine the status of the device and the system. In addition to faults, the nFAULT terminal also signals wake-up requests and a “cold” power-up sequence on the VSUP battery terminal so the system can do any diagnostics or cold booting sequence necessary. The RXD terminal indicates wake-up request and the faults are multiplexed (ORed) to the nFAULT output.
| EVENT | FLAG NAME | CAUSE | INDICATORS(1) | FLAG IS CLEARED | COMMENT |
|---|---|---|---|---|---|
| Power-up | PWRON | Power up on VSUP and any return of VSUP after it has been below UVSUP | nFAULT = low upon entering silent mode from standby or sleep mode | After a transition to normal mode | A cold start condition generates a local wake-up WAKERQ, WAKESR and a PWRON flag. |
| Wake-up Request | WAKERQ(2) | Wake-up event on CAN bus, state transition on WAKE pin, or initial power up | nFAULT = RXD = low after wake-up upon entering standby mode | After a transition to normal mode or VCC < UVCC(F) or VIO < UVIO(F) for t ≥ tUV |
Wake-up request may only be set from
standby, go-to-sleep, or sleep mode. Resets timers for UVVCC or UVVIO. |
| Wake-up Source Recognition(3) | WAKESR | Available upon entering normal mode(4) nFAULT = low indicates a local wake-up event from the WAKE pin nFAULT = high indicates a remote wake-up event from the CAN bus |
After four recessive-to-dominant
edges on TXD in normal mode, leaving normal mode, or VCC < UVCC(F) or VIO < UVIO(F) for t ≥ tUV |
A cold start condition generates a local wake-up WAKERQ, WAKESR and a PWRON flag. | |
| Undervoltage | UVCC | VCC < UVCC(F) | Not externally indicated | VCC >
UVCC(R), or a wake-up request occurs |
|
| UVIO | VIO < UVIO(F) | Not externally indicated | VIO >
UVIO(R), or a wake-up request occurs |
||
| UVSUP | VSUP < UVSUP(F) | Not externally indicated | VSUP > UVSUP(R) | A VSUP undervoltage event generates a cold start condition once VSUP > UVSUP(R) | |
| CAN Bus Fault | CBF | See CAN Bus Fault | nFAULT = low in normal mode only(5) | Upon leaving normal mode, or if no CAN bus fault is detected for four consecutive dominant-to-recessive transitions of the TXD pin while in normal mode |
CAN bus fault must persist for four consecutive dominant-to-recessive transitions |
| Local Faults | TXDCLP | TXD low when CAN active mode is entered | nFAULT = low upon entering silent mode from normal mode | RXD = low & TXD =
high, TXD = high & a mode transition into normal, standby, go-to-sleep, or sleep modes |
CAN driver remains disabled until the TXDCLP is cleared. CAN receiver remains active during the TXDCLP fault |
| TXDDTO | TXD dominant time out, dominant (low) signal for t ≥ tTXDDTO | CAN driver remains disabled until the TXDDTO is cleared. CAN receiver remains active during the TXDDTO fault | |||
| TXDRXD | TXD and RXD pins are shorted together for t ≥ tTXDDTO | CAN driver remains disabled until the TXDRXD is cleared. CAN receiver remains active during the TXDRXD fault | |||
| CANDOM | CAN bus dominant fault, when dominant bus signal received for t ≥ tBUSDOM | RXD = high, or a transition into normal, standby, go-to-sleep, or sleep modes |
CAN driver remains enabled during CANDOM fault | ||
| TSD | Thermal shutdown, TJ ≥ TSDR | TJ < TSDF
and RXD = low & TXD = high, or transition into normal, standby, go-to-sleep, or sleep modes |
CAN driver remains disabled until the TSD event is cleared |