SFFS790 February 2024 TXV0108-Q1
This section provides a Failure Mode Analysis (FMA) for the pins of the TXV0108-Q1 (VQFN package). The failure modes covered in this document include the typical pin-by-pin failure scenarios:
Table 4-2 through Table 4-6 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 |
Pin Diagram (VQFN) Package shows the TXV0108-Q1 pin diagram for the VQFN package. For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the TXV0108-Q1 data sheet.
Following are the assumptions of use and the device configuration assumed for the pin FMA in this section:
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| VCCA | 1 | GND short to VCC, device will be bypassed - may cause system damage, but not device damage | B |
| DIR | 2 | Direction control will fixed, B --> A direction. | B |
| A1 - A8 | 3 to 10 | If configured as an output then damage is possible. If configured as input, no damage, but output will not switch. | A |
| GND | 11 to 13 | Normal operation. | D |
| B8 - B1 | 14 to 21 | If configured as an output then damage is possible. If configured as input, no damage, but output will not switch. | A |
| OE (active low) | 22 | Outputs will remain enabled. | B |
| VCCB | 23 to 24 | GND short to VCC, device will be bypassed - may cause system damage, but not device damage. | B |
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| VCCA | 1 | Device will not be powered. | B |
| DIR | 2 | Pin is floating which can cause excessive current. | A |
| A1 - A8 | 3 to 10 | If configured as output, normal operation. If configured as input, pin is floating which can cause excessive current. | A |
| GND | 11 to 13 | Device will not be powered. | B |
| B8 - B1 | 14 to 21 | If configured as output, normal operation. If configured as input, pin is floating which can cause excessive current. | A |
| OE (active low) | 22 | Pin is floating which can cause excessive current and cause the outputs to switch between enabled and disabled. | B |
| VCCB | 23 to 24 | Device will not be powered. | B |
| Pin Name | Pin No. | Shorted to | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|---|
| VCCA | 1 | DIR | Direction control will fixed, B --> A direction. | B |
| DIR | 2 | A1 | If DIR is LOW, A1 will be an output and damage is possible. If DIR is HIGH, A1 will be an input and drive the output B1 HIGH. | A |
| A(n) | 3 to 9 | A(n+1) | If A(n) and A(n+1) are configured as outputs then damage is possible. If configured as inputs, both bits will have the same value always | A |
| A8 | 10 | GND | If A8 is configured as an output then damage is possible. If configured as input, output B8 will be fixed LOW. | A |
| GND | 11 to 12 | GND | Normal Operation. | D |
| GND | 13 | B8 | If B8 is configured as an output then damage is possible. If configured as input, output A8 will be fixed LOW. | A |
| B(n) | 14 to 20 | B(n+1) | If B(n) and B(n+1) are configured as outputs then damage is possible. If configured as inputs, both bits will have the same value always. | A |
| B1 | 21 | VCCB | If B1 is configured as an output then damage is possible. If configured as an input, no damage, but output A1 will remain HIGH. | A |
| VCCB | 23 to 24 | VCCB | Normal Operation. | D |
| VCCB | 24 | VCCA | VCCB short to VCCA, device will be bypassed - may cause system damage, but not device damage. | B |
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| VCCA | 1 | Normal Operation. | D |
| DIR | 2 | Direction control will fixed, B --> A direction. | B |
| A1 - A8 | 3 to 10 | If configured as an output then damage is possible. If configured as input, no damage, but output will not switch. | A |
| GND | 11 to 13 | GND short to VCC, device will be bypassed. This can cause system damage, but not device damage. | B |
| B8 - B1 | 14 to 21 | If configured as an output then damage is possible. If configured as input, damage is possible if VIH/VIL is not met. | A |
| OE (active low) | 22 | Outputs will remain disabled. | B |
| VCCB | 23 to 24 | VCCB short to VCCA, device will be bypassed. This can cause system damage, but not device damage. | B |
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| VCCA | 1 | VCCB short to VCCA, device will be bypassed. This can cause system damage, but not device damage. | B |
| DIR | 2 | If VCCA > VCCB, then the direction control will fix A-->B, If VCCA < VCCB, damage is possible if VIH/VIL is not met. | A |
| A1 - A8 | 3 to 10 | If configured as an output then damage is possible. If configured as input, damage is possible if VIH/VIL not met. | A |
| GND | 11 to 13 | GND short to VCC, device will be bypassed. This can cause system damage, but not device damage. | B |
| B8 - B1 | 14 to 21 | If configured as an output then damage is possible. If configured as input, no damage, but output will not switch. | A |
| OE (active low) | 22 | If VCCA > VCCB, then the outputs will remain disabled, If VCCA < VCCB, damage is possible if VIH/VIL is not met. | A |
| VCCB | 23 to 24 | Normal operation. | D |