TCAN1043N-Q1 and
TCAN1473-Q1
Functional Safety
FIT Rate, FMD, and Pin FMA
Trademarks
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1 Overview
This document contains information for the TCAN1043N-Q1 and TCAN1473-Q1 to aid in a functional safety system design. This is a controller area network (CAN) transceiver in the SOIC (D), VSON (DMT), and SOT (DYY) packages to aid in a functional safety system design. Information provided are:
- Functional safety failure in time (FIT) rates of the semiconductor component estimated by the application of industry reliability standards
- Component failure modes and their distribution (FMD) based on the primary function of the device
- Pin failure mode analysis (FMA) for the device pins of TCAN1043N-Q1 and TCAN1473-Q1
Figure 1-1 shows the device functional block diagram for reference.
Figure 1-1 TCAN1043N-Q1 and TCAN1473-Q1 Functional Block Diagram2 Functional Safety Failure In Time (FIT) Rates
This section provides functional safety failure in time (FIT) rates for TCAN1043N-Q1 and TCAN1473-Q1 based on two different industry-wide used reliability standards:
- Table 2-1 provides FIT rates based on IEC TR 62380 / ISO 26262 part 11
- Table 2-2 provides FIT rates based on the Siemens Norm SN 29500-2
| FIT IEC TR 62380 / ISO 26262 | FIT (Failures Per 109 Hours) 14-pin SOIC (D) | FIT (Failures Per 109 Hours) 14-pin VSON (DMT) | FIT (Failures Per 109 Hours) 14-pin SOT (DYY) |
|---|---|---|---|
| Total component FIT rate | 22 | 10 | 11 |
| Die FIT rate | 6 | 4 | 7 |
| Package FIT rate | 16 | 6 | 4 |
The failure rate and mission profile information in Table 2-1 comes from the reliability data handbook IEC TR 62380 / ISO 26262 part 11:
- Mission profile: Motor control from table 11
- Power dissipation: 353mW
- Climate type: World-wide table 8
- Package factor (lambda 3): Table 17b
- Substrate material: FR4
- EOS FIT rate assumed: 0 FIT
| Table | Category | Reference FIT Rate | Reference Virtual TJ |
|---|---|---|---|
| 5 | CMOS/BICMOS ASICs analog and mixed ≤ 50V supply | 25 FIT | 55°C |
The reference FIT rate and reference virtual TJ (junction temperature) in Table 2-2 come from the Siemens Norm SN 29500-2 tables 1 through 5. Failure rates under operating conditions are calculated from the reference failure rate and virtual junction temperature using conversion information in SN 29500-2 section 4.
3 Failure Mode Distribution (FMD)
The failure mode distribution estimation for TCAN1043N-Q1 and TCAN1473-Q1 in Table 3-1 comes from the combination of common failure modes listed in standards such as IEC 61508 and ISO 26262, the ratio of sub-circuit function size and complexity, and from best engineering judgment.
The failure modes listed in this section reflect random failure events and do not include failures resulting from misuse or overstress.
| Die Failure Modes | Failure Mode Distribution (%) |
|---|---|
| Receiver fail | 35 |
| Transmitter fail | 35 |
| System stuck in sleep mode | 15 |
| Control and mode logic failure | 10 |
| CANL or CANH driver stuck dominant | 5 |
4 Pin Failure Mode Analysis (Pin FMA)
This section provides a failure mode analysis (FMA) for the pins of the TCAN1043N-Q1 and TCAN1473-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 VCC (see Table 4-5)
- Pin short-circuited to VSUP (see Table 4-6)
- Pin short-circuited to VIO (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.
| 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 SOIC (D) pin diagram. Figure 4-2 shows the VSON (DMT) pin diagram. Figure 4-3 shows the SOT (DYY) pin diagram.
For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the TCAN1043N-Q1 and TCAN1473-Q1 data sheets.
Figure 4-1 SOIC (D) Pin Diagram
Figure 4-2 VSON (DMT) Pin Diagram
Figure 4-3 SOT
(DYY) Pin DiagramFollowing 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
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | TXD biased dominant indefinitely. The device enters dominant time-out mode. Unable to transmit data. | B |
| GND | 2 | None. | D |
| VCC | 3 | Device enters Sleep mode. There is a high current draw from the external regulator that supplies to the VCC pin. | B |
| RXD | 4 | Receiver output biased recessive indefinitely. The host is unable to receive data from the bus. | B |
| VIO | 5 | Device enters Sleep mode. Transceiver is passive on bus. There is a high current draw from the external regulator that supplies to VIO. | B |
| EN | 6 | EN pin biased low. The device is not able to enter normal mode. Unable to communicate. | B |
| INH | 7 | High ISUP current, the INH pin can be damaged and indication from sleep mode transition is not available. | A |
| nFAULT | 8 | nFAULT pin biased low indefinitely, which indicates a fault indefinitely. | B |
| WAKE | 9 | WAKE pin biased low indefinitely and is not able to utilize the local wake-up function. | B |
| VSUP | 10 | Device is not powered. There will be a high current flowing from the source supplying to the VSUP pin (battery) to the ground. | B |
| NC | 11 | None. | D |
| CANL | 12 | VO(REC) specification is violated, degraded EMC performance. | C |
| CANH | 13 | Device cannot drive dominant bit to the bus, no communication possible. | B |
| nSTB | 14 | nSTB biased low indefinitely. The transceiver is unable to enter normal mode. Unable to communicate. | B |
| Thermal Pad | - | None. | D |
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | TXD pin defaults to a recessive bias. The device is always recessive and unable to transmit data. | B |
| GND | 2 | Device is not powered. | B |
| VCC | 3 | Device is in protected mode. | B |
| RXD | 4 | No RXD output, unable to receive data. | B |
| VIO | 5 | Device is in protected mode. | B |
| EN | 6 | EN pin defaults to a logic-low bias. The device is not able to enter normal mode. Unable to communicate. | B |
| INH | 7 | None. | D |
| nFAULT | 8 | No effect on the device performance, unable to monitor system faults. | B |
| WAKE | 9 | No effect on the device performance, unable to use the local wake-up function. | B |
| VSUP | 10 | Device is not powered. | B |
| NC | 11 | None. | D |
| CANL | 12 | Device cannot drive dominant on bus and is unable to communicate. | B |
| CANH | 13 | Device cannot drive dominant on bus and is unable to communicate. | B |
| nSTB | 14 | nSTB defaults to a logic-low bias. The device is not able to enter normal mode. Unable to communicate. | B |
| Thermal Pad | - | None. | D |
| Pin Name | Pin No. | Shorted to | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|---|
| TXD | 1 | GND | TXD is biased dominant indefinitely. The device enters dominant time-out mode. Unable to transmit data. | B |
| GND | 2 | VCC | Device is in protected mode, high ICC current. | B |
| VCC | 3 | RXD | RXD output biased recessive indefinitely. The controller is unable to receive data from CAN bus. | B |
| RXD | 4 | VIO | RXD output biased recessive indefinitely. The controller is unable to receive data from CAN bus. | B |
| VIO | 5 | EN | EN pin biased high indefinitely. The device is unable to enter standby and silent mode. | B |
| EN | 6 | INH | Absolute maximum violation on the EN pin, except in sleep mode. Transceiver can be damaged. | A |
| nFAULT | 8 | WAKE | Potential absolute maximum violation on nFAULT pin if WAKE is biased high. Transceiver can be damaged. | A |
| WAKE | 9 | VSUP | WAKE biased high indefinitely, unable to utilize the local wake-up function. | B |
| VSUP | 10 | NC | None. | D |
| NC | 11 | CANL | None. | D |
| CANL | 12 | CANH | Bus biased recessive. No communication is possible. IOS current can be reached on CANH/CANL. | B |
| CANH | 13 | nSTB | Driver and receiver turn off when the CAN bus is recessive. Potentially does not enter normal mode. | B |
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | TXD biased recessive indefinitely, unable to transmit data. | B |
| GND | 2 | CAN transmitter is not powered and the device enters Sleep mode. There is a high current draw from the external regulator supplying to the VCC pin. | B |
| VCC | 3 | None. | D |
| RXD | 4 | Receiver output biased recessive indefinitely. Host is unable to receive data from bus. | B |
| VIO | 5 | I/O pins operate as 5V inputs and outputs. Microcontroller can be damaged if VCC > VIO. | C |
| EN | 6 | EN biased high indefinitely. The device is unable to enter standby and silent mode. | B |
| INH | 7 | Absolute maximum violation on VCC pin. INH is biased at VCC voltage. System potentially does not wake up. | A |
| nFAULT | 8 | nFAULT biased high indefinitely. The transceiver is unable to report faults. | B |
| WAKE | 9 | None. | D |
| VSUP | 10 | Absolute maximum violation on VCC. | A |
| NC | 11 | None. | D |
| CANL | 12 | IOS current can be reached, RXD is always recessive. | B |
| CANH | 13 | VO(REC) specification is violated, degraded EMC performance. | C |
| nSTB | 14 | nSTB biased high indefinitely. The transceiver is unable to enter standby and sleep mode. | B |
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | Absolute maximum violation, transceiver can be damaged. | A |
| GND | 2 | Device is not powered, high ISUP current. | B |
| VCC | 3 | Absolute maximum violation, transceiver can be damaged. | A |
| RXD | 4 | Absolute maximum violation, transceiver can be damaged. | A |
| VIO | 5 | Absolute maximum violation, transceiver can be damaged. | A |
| EN | 6 | Absolute maximum violation, transceiver can be damaged. | A |
| INH | 7 | Minimal current driven into the INH pin. | D |
| nFAULT | 8 | Absolute maximum violation, transceiver can be damaged. | A |
| WAKE | 9 | WAKE biased high, unable to use the local wake-up function. | B |
| VSUP | 10 | None. | D |
| NC | 11 | None. | D |
| CANL | 12 | IOS current can be reached. RXD is always recessive. | B |
| CANH | 13 | VO(REC) specification is violated, degraded EMC performance and communication errors can also result. | C |
| nSTB | 14 | Absolute maximum violation, transceiver can be damaged. | A |
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| TXD | 1 | TXD biased recessive indefinitely, unable to transmit data. | B |
| GND | 2 | Device is not powered. There is a high current draw from the external regulator supplying to the VIO pin. | B |
| VCC | 3 | I/O pins operate as 5V inputs and outputs. Microcontroller can be damaged if VCC > VIO. | C |
| RXD | 4 | Receiver output biased recessive indefinitely. Host is unable to receive data from bus. | B |
| VIO | 5 | None. | D |
| EN | 6 | EN biased high indefinitely. The device is unable to enter standby and silent mode. | B |
| INH | 7 | Absolute maximum violation on the VIO pin. INH is biased at VIO voltage. System potentially does not wake up. | A |
| nFAULT | 8 | nFAULT biased high indefinitely. The transceiver is unable to report faults. | B |
| WAKE | 9 | None. | D |
| VSUP | 10 | Absolute maximum violation on VIO. | A |
| NC | 11 | None. | D |
| CANL | 12 | IOS current can be reached, RXD is always recessive. | B |
| CANH | 13 | VO(REC) specification is violated, degraded EMC performance. | C |
| nSTB | 14 | nSTB biased high indefinitely. The transceiver is unable to enter standby and sleep mode. | B |
5 Revision History
| DATE | REVISION | NOTES |
|---|---|---|
| December 2024 | * | Initial Release |
