SFFS743 November 2023 TPS3840
This section provides a failure mode analysis (FMA) for the pins of the TPS3840. 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 TPS3840 pin diagram. For a detailed description of the device pins, see the Pin Configuration and Functions section in the TPS3840 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 Effects | Failure Effect Class |
---|---|---|---|
RESET | 1 | Forces RESET to be held low. | B |
VDD | 2 | VDD short to GND Fault. The device is non-operational. | B |
GND | 3 | No damage to device. No impact to functionality. | D |
MR / NC | 4 | Normal operation. RESET will be asserted. | B |
CT | 5 | RESET is forced and held low when VDD goes below threshold. Device is non-operational. | B |
Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
---|---|---|---|
RESET | 1 | Unreliable reset output functionality. | B |
VDD | 2 | The device is unpowered and non-operational. | B |
GND | 3 | The RESET and VDD are both held low. | B |
MR / NC | 4 | Normal Operation. This pin can be left floating. | D |
CT | 5 | Normal Operation. This pin can be left floating. | D |
Pin Name | Pin No. | Shorted to | Description of Potential Failure Effects | Failure Effect Class |
---|---|---|---|---|
RESET | 1 | VDD | Large current can flow into RESET when in error condition. This can cause permanent damage. | A |
VDD | 2 | GND | The device is non-operational. | B |
GND | 3 | MR / NC | Normal operation. RESET will be asserted. | B |
MR / NC | 4 | CT | RESET is forced and held low when VDD goes below threshold. Device is non-operational. | B |
CT | 5 | RESET | RESET is forced and held low when VDD goes below threshold. Device is non-operational. | B |
Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
---|---|---|---|
RESET | 1 | Large current can flow into RESET when in error condition. This can cause permanent damage. | A |
VDD | 2 | Normal operation. | D |
GND | 3 | VDD short to GND fault. Device is non-operational. | B |
MR / NC | 4 | Normal operation. | D |
CT | 5 | Forces RESET to be held low. Device is non-operational. | B |