SFFSA17 October 2024 TCAN1473A-Q1
4 Pin Failure Mode Analysis (Pin FMA)
This section provides a failure mode analysis (FMA) for the pins of the TCAN1473A-Q1. The failure modes covered in this document include the typical pin-by-pin failure scenarios:
- Pin short-circuited to ground (see Table 4-2)
- Pin open-circuited (see Table 4-3)
- Pin short-circuited to an adjacent pin (see Table 4-4)
- Pin short-circuited to VSUP (see Table 4-5)
- Pin short-circuited to VCC (see Table 4-6)
- Pin short-circuited to VIO (see Table 4-7)
Table 4-2 through Table 4-7 also indicate how these pin conditions can affect the device as per the failure effects classification in Table 4-1.
Table 4-1 TI Classification of Failure Effects
| Class | Failure Effects |
|---|---|
| A | Potential device damage that affects functionality. |
| B | No device damage, but loss of functionality. |
| C | No device damage, but performance degradation. |
| D | No device damage, no impact to functionality or performance. |
Figure 4-1 shows the TCAN1473A-Q1 pin diagram for the 14-pin SOIC (D) and 14-pin SOT (DYY) packages. Figure 4-2 shows the TCAN1473A-Q1 pin diagram for the 14-pin VSON (DMT) package. For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the TCAN1473A-Q1 data sheet.
Figure 4-1 TCAN1473A-Q1 Pin Diagram (14-pin SOIC (D) and 14-pin SOT (DYY)
Packages)
Figure 4-2 TCAN1473A-Q1 Pin Diagram (14-pin VSON (DMT) Package)Following are the assumptions of use and the device configuration assumed for the pin FMA in this section:
- VCC = 4.5V to 5.5V
- VSUP = 4.5V to 40V
- VIO = 1.7V to 5.5V
Table 4-2 Pin FMA for Device Pins Short-Circuited to Ground
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | The TXD pin is biased dominant indefinitely. The device enters dominant time-out mode. The device is unable to transmit data. | B |
| GND | 2 | None | D |
| VCC | 3 | The device enters sleep mode. There is a high current draw from the external regulator supplying the VCC pin. | B |
| RXD | 4 | The output of the receiver is biased recessive indefinitely. The host is unable to receive data from the bus. | B |
| VIO | 5 | The device enters sleep mode. The transceiver is passive on the bus. There is a high current draw from the external regulator supplying the VIO pin. | B |
| EN | 6 | The EN pin is biased low. The device is unable to enter normal mode. The device is unable to communicate. | B |
| INH | 7 | The ISUP current is high. The INH pin is potentially damaged and indication from the transition to sleep mode is not available. | A |
| nFAULT | 8 | The nFAULT pin is biased low indefinitely, which indicates a fault indefinitely. | B |
| WAKE | 9 | The WAKE pin is biased low indefinitely and is unable to utilize the local wake-up function. | B |
| VSUP | 10 | The device is not powered. There is a high current flowing from the source supplying VSUP flowing to GND. | B |
| INH_MASK | 11 | The inhibit mask function cannot be used as intended. | B |
| CANL | 12 | There is a violation of the VO(REC) specification. EMC performance is degraded. | C |
| CANH | 13 | The device cannot drive the dominant bit to the bus, communication is not possible. | B |
| nSTB | 14 | The nSTB pin is biased low indefinitely. The transceiver is unable to enter normal mode. The device is unable to communicate. | B |
| Thermal Pad | - | None | D |
Note: The 14-pin VSON (DMT) package includes a thermal pad.
Table 4-3 Pin FMA for Device Pins Open-Circuited
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | The TXD pin defaults to a recessive bias. The device is always recessive and unable to transmit data. | B |
| GND | 2 | The device is not powered. | B |
| VCC | 3 | The device in protected mode. | B |
| RXD | 4 | There is no RXD output, the device is unable to receive data. | B |
| VIO | 5 | The device in protected mode. | B |
| EN | 6 | The EN pin defaults to a logic-low bias. The device is unable to enter normal mode. The device is unable to communicate. | B |
| INH | 7 | None | D |
| nFAULT | 8 | There is no effect on performance, but the device is unable to monitor system faults. | B |
| WAKE | 9 | There is no effect on performance, but the device is unable to utilize the local wake-up function. | B |
| VSUP | 10 | The device is not powered. | B |
| INH_MASK | 11 | The inhibit mask function cannot be used as intended. | B |
| CANL | 12 | The device cannot drive dominant on the bus. The device is unable to communicate. | B |
| CANH | 13 | The device cannot drive dominant on the bus. The device is unable to communicate. | B |
| nSTB | 14 | The nSTB pin defaults to a logic-low bias. The device is unable to enter normal mode. The device is unable to communicate. | B |
| Thermal Pad | - | None | D |
Note: The 14-pin VSON (DMT) package includes a thermal pad.
Table 4-4 Pin FMA for Device Pins Short-Circuited to Adjacent Pin
| Pin Name | Pin No. | Shorted to | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|---|
| TXD | 1 | GND | The TXD pin is biased dominant indefinitely and the device enters dominant time-out mode. The device is unable to transmit data. | B |
| GND | 2 | VCC | The device is in protected mode, the ICC current is high. | B |
| VCC | 3 | RXD | The output of the RXD pin is biased recessive indefinitely. The controller is unable to receive data from the CAN bus. | B |
| RXD | 4 | VIO | The output of the RXD pin is biased recessive indefinitely. The controller is unable to receive data from the CAN bus. | B |
| VIO | 5 | EN | The EN pin is biased high indefinitely. The device is unable to enter the standby and silent modes. | B |
| EN | 6 | INH | There is a violation of the absolute maximum rating on the EN pin (except in sleep mode). The transceiver is potentially damaged. | A |
| nFAULT | 8 | WAKE | There is a potential violation of the absolute maximum rating on the nFAULT pin if WAKE is biased high. The transceiver is potentially damaged. | A |
| WAKE | 9 | VSUP | The WAKE pin is biased high indefinitely, the device is unable to utilize local wake-up function. | B |
| VSUP | 10 | INH_MASK | There is a violation of the absolute maximum rating on the INH_MASK pin. The transceiver is potentially damaged. | A |
| INH_MASK | 11 | CANL | If the INH_MASK pin is at VIO level, the IOS
current is potentially reached; RXD is always recessive. If the INH_MASK pin is at logic low, the O(REC) specifications are violated. EMC performance is degraded. | B |
| CANL | 12 | CANH | The bus is biased recessive. Communication is not possible. The IOS current is potentially reached on the CANH or CANL pin. | B |
| CANH | 13 | nSTB | The driver and receiver turn off when the CAN bus is recessive. The device potentially does not enter normal mode. | B |
Note: The 14-pin VSON (DMT) package includes a thermal pad. All devices pins are adjacent to the
thermal pad. The behavior of the device when pins are shorted to the thermal pad
depends on the net that is connected to the thermal pad.
Table 4-5 Pin FMA for Device Pins Short-Circuited to VSUP
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | There is a violation of the absolute maximum rating. The transceiver is potentially damaged. | A |
| GND | 2 | The device is not powered. The ISUP current is high. | B |
| VCC | 3 | There is a violation of the absolute maximum rating. The transceiver is potentially damaged. | A |
| RXD | 4 | There is a violation of the absolute maximum rating. The transceiver is potentially damaged. | A |
| VIO | 5 | There is a violation of the absolute maximum rating. The transceiver is potentially damaged. | A |
| EN | 6 | There is a violation of the absolute maximum rating. The transceiver is potentially damaged. | A |
| INH | 7 | Minimal current is driven into the INH pin. | D |
| nFAULT | 8 | There is a violation of the absolute maximum rating. The transceiver is potentially damaged. | A |
| WAKE | 9 | The WAKE pin is biased high. The device is unable to utilize the local wake-up function. | B |
| VSUP | 10 | None | D |
| INH_MASK | 11 | There is a violation of the absolute maximum rating. The transceiver is potentially damaged. | A |
| CANL | 12 | The IOS current is potentially reached. The RXD pin is always recessive. | B |
| CANH | 13 | The VO(REC) specification is violated. EMC performance is degraded and communication errors potentially result. | C |
| nSTB | 14 | There is a violation of the absolute maximum rating. The transceiver is potentially damaged. | A |
Note: The 14-pin VSON (DMT) package includes a thermal pad.
Table 4-6 Pin FMA for Device Pins Short-Circuited to VCC
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | The TXD pin is biased recessive indefinitely. The device is unable to transmit data. | B |
| GND | 2 | The CAN transmitter is not powered and the device enters sleep mode. There is a high current draw from the external regulator supplying the VCC pin. | B |
| VCC | 3 | None | D |
| RXD | 4 | The output of the receiver is biased recessive indefinitely. The host is unable to receive data from the bus. | B |
| VIO | 5 | The I/O pins operate as 5V input and output pins. The microcontroller is potentially damaged if VCC > VIO. | C |
| EN | 6 | The EN pin is biased high indefinitely. The device is unable to enter the standby and silent modes. | B |
| INH | 7 | There is a violation of the absolute maximum rating on the VCC pin. The INH pin is biased at the VCC voltage. The system potentially does not wakeup. | A |
| nFAULT | 8 | The nFAULT pin is biased high indefinitely. The transceiver is unable to report faults. | B |
| WAKE | 9 | None | D |
| VSUP | 10 | There is a violation of the absolute maximum rating on the VCC pin. | A |
| INH_MASK | 11 | The inhibit mask function is activated when the device enters silent mode. The microcontroller is potentially damaged if VCC > VIO. | B |
| CANL | 12 | The IOS current is potentially reached. The RXD pin is always recessive. | B |
| CANH | 13 | The VO(REC) specification is violated. EMC performance is degraded. | C |
| nSTB | 14 | The nSTB pin is biased high indefinitely. The transceiver is unable to enter the standby and sleep modes. | B |
Note: The 14-pin VSON (DMT) package includes a thermal pad.
Table 4-7 Pin FMA for Device Pins Short-Circuited to VIO
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | The TXD pin is biased recessive indefinitely. The device is unable to transmit data. | B |
| GND | 2 | The device is not powered. There is a high current draw from the external regulator supplying to the VIO pin. | B |
| VCC | 3 | The I/O pins operate as 5V input and outputs pins. The microcontroller is potentially damaged if VCC > VIO. | C |
| RXD | 4 | The output of the receiver is biased recessive indefinitely. The host is unable to receive data from bus. | B |
| VIO | 5 | None | D |
| EN | 6 | The EN pin is biased high indefinitely. The device is unable to enter the standby and silent modes. | B |
| INH | 7 | There is a violation of the absolute maximum rating on the VIO pin. The INH pin is biased at the VIO voltage. The system potentially does not wakeup. | B |
| nFAULT | 8 | The nFAULT pin is biased high indefinitely. The transceiver is unable to report faults. | B |
| WAKE | 9 | None | D |
| VSUP | 10 | There is a violation of the absolute maximum rating on the VIO pin. | A |
| INH_MASK | 11 | The inhibit mask function is activated when the device enters silent mode. | D |
| CANL | 12 | The IOS current is potentially reached. The RXD pin is always recessive. | B |
| CANH | 13 | The VO(REC) specification is violated. EMC performance is degraded. | C |
| nSTB | 14 | The nSTB pin is biased high indefinitely. The transceiver is unable to enter the standby and sleep modes. | B |