SFFS338 March 2022 TPS62441 , TPS62442
This section provides a Failure Mode Analysis (FMA) for the pins of the TPS6244x. The failure modes covered in this document include the typical pin-by-pin failure scenarios:
Table 4-2 through Table 4-5 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 TPS6244x pin diagram. For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the TPS6244x data sheet.
Following are the assumptions of use and the device configuration assumed for the pin FMA in this section:
Assumption the device is running in the typical application, please refer to the 'Simplified Schematics' on the first page in the TPS6244x data sheet.
Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
---|---|---|---|
FB2 | 1 | Converter 2 output voltage regulated to VIN (100% mode) | B |
GND | 2 | No effect, normal operation | D |
FB1 | 3 | Converter 1 output voltage regulated to VIN (100% mode) | B |
PG1 | 4 | No operation, no power-good indication | B |
MODE/SYNC | 5 | Intended functionality | D |
SW1 | 6 | Potential device damage | A |
VIN1 | 7 | Converter 1 does not power up. No output voltage on converter 1 | B |
EN1 | 8 | Converter 1 is disabled. No output voltage on converter 1 | B |
GND | 9 | No effect, normal operation | D |
EN2 | 10 | Converter 2 is disabled. No output voltage on converter 2 | B |
VIN2 | 11 | Converter 2 does not power up. No output voltage on converter 2 | B |
SW2 | 12 | Potential device damage | A |
PG2 | 13 | No operation, no power-good indication | B |
COMP/FSET | 14 | Intended functionality, device operates in fixed frequency. | D |
Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
---|---|---|---|
FB2 | 1 | Undetermined output voltage behavior of converter 2; open loop operation | B |
GND | 2 | Device does not power up. No output voltage | B |
FB1 | 3 | Undetermined output voltage behavior of converter 1; open loop operation | B |
PG1 | 4 | Intended functionality | B |
MODE/SYNC | 5 | Undetermined device operation | B |
SW1 | 6 | Output voltage 1 not functional, open loop operation | B |
VIN1 | 7 | Converter 1 does not power up. | B |
EN1 | 8 | Undetermined device operation; converter 1 might power up or not. | B |
GND | 9 | Device does not power up. No output voltage | B |
EN2 | 10 | Undetermined device operation; converter 2 might power up or not. | B |
VIN2 | 11 | Converter 2 does not power up. | B |
SW2 | 12 | Converter 2 is not functional. Open loop operation | B |
PG2 | 13 | Intended functionality | B |
COMP/FSET | 14 | Normal operation | D |
Pin Name | Pin No. | Shorted to | Description of Potential Failure Effect(s) | Failure Effect Class |
---|---|---|---|---|
FB1 | 3 | PG1 | Converter 2 does not regulate. | B |
PG1 | 4 | MODE/SYNC | No device damage, but performance degradation | B |
MODE/SYNC | 5 | SW1 | Potential internal device damage | A |
SW2 | 12 | PG2 | Potential internal device damage | A |
PG2 | 13 | COMP/FSET | Potential internal device damage | A |
COMP/FSET | 14 | FB2 | Converter 2 does not regulate. | B |
Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
---|---|---|---|
FB2 | 1 | Potential device damage | A |
GND | 2 | Device does not power up. No output voltage | B |
FB1 | 3 | Potential device damage | A |
PG1 | 4 | Potential device damage | A |
MODE/SYNC | 5 | Intended functionality; FPWM mode | D |
SW1 | 6 | Potential device damage | A |
VIN1 | 7 | Normal operation | D |
EN1 | 8 | Intended functionality; converter 1 enable | D |
GND | 9 | Device does not power up. No output voltage | B |
EN2 | 10 | Intended functionality; converter 2 enable | D |
VIN2 | 11 | Normal operation | D |
SW2 | 12 | Potential device damage | A |
PG2 | 13 | Potential device damage | A |
COMP/FSET | 14 | Intended functionality; device operates in fixed frequency. | D |