SFFS372 February   2022 TPS74801-Q1

 

  1.   Trademarks
  2. 1Overview
  3. 2Functional Safety Failure In Time (FIT) Rates
    1. 2.1 VQFN Package
    2. 2.2 VSON Package
  4. 3Failure Mode Distribution (FMD)
  5. 4Pin Failure Mode Analysis (Pin FMA)
    1. 4.1 VQFN Package
    2. 4.2 VSON Package

Pin Failure Mode Analysis (Pin FMA)

This section provides a failure mode analysis (FMA) for the pins of the TPS74801-Q1 (VQFN and VSON packages). The failure modes covered in this document include the typical pin-by-pin failure scenarios:

Table 4-2 through Table 4-9 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
ClassFailure Effects
APotential device damage that affects functionality
BNo device damage, but loss of functionality
CNo device damage, but performance degradation
DNo device damage, no impact to functionality or performance

Following are the assumptions of use and the device configuration assumed for the pin FMA in this section:

  • External pullup resistor on CS to VDD
  • RC filter on every analog input, AINx.

    Series resistors are sized to limit the input currents into the analog inputs to <10 mA in all circumstances (for example, in case the device is unpowered and the input signal is applied).

  • The device is the only slave on the SPI bus.