SFFS791 February 2024 TXU0101-Q1

4 Pin Failure Mode Analysis (Pin FMA)

This section provides a Failure Mode Analysis (FMA) for the pins of the TXU0101-Q1 (SC70 and SON 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)
Pin open-circuited (see Table 4-3)
Pin short-circuited to an adjacent pin (see Table 4-4)
Pin short-circuited to supply (see Table 4-5 and Table 4-6)

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.

Table 4-1 TI Classification of Failure Effects

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

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

Pin short-circuited to Ground (see Table 4-2)
Pin open-circuited (see Table 4-3)
Pin short-circuited to an adjacent pin (see Table 4-4)
Pin short-circuited to supply (see Table 4-5 and Table 4-6)

Figure 4-1 and Figure 4-2 shows the TXU0101-Q1 pin diagram for the SC70 and SON packages. For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the TXU0101-Q1 data sheet.

Figure 4-1 Pin Diagram (SC70) Package

Figure 4-2 Pin Diagram (SON) Package

Table 4-2 Pin FMA for Device Pins Short-Circuited to Ground

Pin Name	Pin No.	Description of Potential Failure Effect(s)	Failure Effect Class
VCCA	1	Device will not be powered or damaged, because short is external to device. System level damage can occur in this scenario.	B
GND	2	Normal operation.	D
A	3	A will be LOW, if corresponding B is HIGH, there will be potential damage to the device if the current is not limited. If corresponding B is LOW, then nothing will occur; there is no damage.	B
BY	4	B will be LOW, if corresponding A is HIGH, there will be potential damage to the device if the current is not limited. If corresponding A is LOW, then nothing will occur; there is no damage.	B
OE	5	All I/Os will be fixed into high impedance (tri-state).	B
VCCB	6	Device will not be powered or damaged, because short is external to device. System level damage may occur in this scenario.	B

Table 4-3 Pin FMA for Device Pins Open-Circuited

Pin Name	Pin No.	Description of Potential Failure Effect(s)	Failure Effect Class
VCCA	1	Device will not be powered.	B
GND	2	Device will not be powered.	B
A	3	A pin will be grounded internally.	D
BY	4	B pin will be in HiZ if device is disabled. If device is enabled, it will be high or LOW depending on the input.	D
OE	5	All I/Os will be fixed into high impedance (tri-state).	A
VCCB	6	Device will not be powered.	B

Table 4-4 Pin FMA for Device Pins Short-Circuited to Adjacent Pin

Pin Name	Pin No.	Shorted to	Description of Potential Failure Effect(s)	Failure Effect Class
VCCA	1	GND	Device will not be powered or damaged, because short is external to device. System level damage may occur in this scenario.	B
GND	2	A	A will be LOW, if corresponding B is HIGH, there will be potential damage to the device if the current is not limited. If corresponding B is LOW, then nothing will occur, no damage.	B
A	3	BY	One input on VCCA supply is shorted to one output of VCCB supply. Based on the external bus driving this connection, potential high current can be expected if the VILA is less than Input Voltage A is less than VIHA or if BY output gets an undeterministic voltage forced on it in presence of a valid input.	A
BY	4	OE	B pin will in HiZ if device is disabled. If device is enabled, it will be HIGH or LOW depending upon the input.	D
OE	5	VCCB	All I/Os will be active, device cannot be disabled.	B
VCCB	6	VCCA	Device will not be powered or damaged, because short is external to device. System level damage may occur in this scenario.	B

Table 4-5 Pin FMA for Device Pins Short-Circuited to supply (VCCA)

Pin Name	Pin No.	Description of Potential Failure Effect(s)	Failure Effect Class
VCCA	1	Normal operation.	D
GND	2	Device will not be powered or damaged, because short is external to device. System level damage may occur in this scenario.	B
A	3	Ax will be HIGH, if corresponding Bx is LOW, there will be potential damage to the device if the current is not limited. If corresponding Bx is HIGH, then nothing will occur, no damage.	B
BY	4	Bx will be HIGH, if corresponding Ax is LOW, there will be potential damage to the device if the current is not limited. If corresponding Ax is HIGH, then nothing will occur; there is no damage.	B
OE	5	All I/Os will be active, device cannot be disabled.	B
VCCB	6	Device will not be powered or damaged, because short is external to device. System level damage may occur in this scenario.	B

Table 4-6 Pin FMA for Device Pins Short-Circuited to supply VCCB

Pin Name	Pin No.	Description of Potential Failure Effect(s)	Failure Effect Class
VCCA	1	Device will not be powered or damaged, because short is external to device. System level damage may occur in this scenario.	B
GND	2	Device will not be powered or damaged, because short is external to device. System level damage may occur in this scenario.	B
A	3	Ax will be HIGH, if corresponding Bx is HIGH, there will be potential damage to the device if the current is not limited. If corresponding Bx is HIGH, then nothing will occur; there is no damage.	B
BY	4	Bx will be HIGH, if corresponding Ax is LOW, there will be potential damage to the device if the current is not limited. If corresponding Ax is HIGH, then nothing will occur; there is no damage.	B
OE	5	All I/Os will be active, device cannot be disabled.	B
VCCB	6	Normal operation.	D