4 Pin Failure Mode Analysis (Pin FMA)

This section provides a failure mode analysis (FMA) for the pins of the UCC27289 (SOIC and VSON packages). The failure modes covered in this document include the typical pin-by-pin failure scenarios:

• Pin short-circuited to ground (see Table 4-2 and Table 4-6)
• Pin open-circuited (see Table 4-3 and Table 4-7)
• Pin short-circuited to an adjacent pin (see Table 4-4 and Table 4-8)
• Pin short-circuited to supply (see Table 4-5 and Table 4-9)

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.

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

• SOIC: Pins 1-4, short to VDD is considered
• SOIC: Pins 5-6, short to 5V, such as, MCU or controller I/O supply is considered
• SOIC: VSS is assumed to be a ground plane
• VSON: Pins 1-5 and 10, short to VDD is considered
• VSON: Pins 6-8, short to 5V, such as, MCU or controller I/O supply is considered
• VSON: VSS is assumed to be a ground plane