SFFS137 April   2021 LDC3114-Q1

 

  1.   Trademarks
  2. 1Overview
  3. 2Functional Safety Failure In Time (FIT) Rates
  4. 3Failure Mode Distribution (FMD)
  5. 4Pin Failure Mode Analysis (Pin FMA)

Pin Failure Mode Analysis (Pin FMA)

This section provides a Failure Mode Analysis (FMA) for the pins of the LDC3114-Q1. 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)

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.

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

Figure 4-1 shows the LDC3114-Q1 pin diagram. For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the LDC3114-Q1 data sheet.

GUID-20200924-CA0I-KL0B-RPMG-FFK192RN4CMG-low.gifFigure 4-1 Pin Diagram

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

  • Device is powered within published absolute maximum operating conditions.

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

COM

1

COM is grounded without a bypass capacitor. Will cause an error in sensor input and unpredictable LC sensor behavior

B

GND

2

Normal operation

D

LPWRB

3

Device stuck in Low Power Mode

B

VDD

4

Power supply shorted to ground

B

INTB

5

INTB is stuck low

B

IN3

6

No LC sensor input

B

IN2

7

No LC sensor input

B

IN1

8

No LC sensor input

B

IN0

9

No LC sensor input

B

GND

10

Normal operation

D

OUT3

11

May result in output status error

B

OUT2

12

May result in output status error

B

OUT1

13

May result in output status error

B

SDA

14

SDA will be stuck low. I2C read/write will be non-functional

B

OUT0

15

May result in output status error

B

SCL

16

SCL will be stuck low. I2C read/write will be non-functional

B

Table 4-3 Pin FMA for Device Pins Open-Circuited
Pin Name Pin No. Description of Potential Failure Effect(s) Failure Effect Class

COM

1

No common return path for LC resonator sensors

B

GND

2

No power supply to device

B

LPWRB

3

Failure to set functional mode

B

VDD

4

No power supply to device

B

INTB

5

INTB does not assert for button presses or error conditions

B

IN3

6

No LC sensor input

B

IN2

7

No LC sensor input

B

IN1

8

No LC sensor input

B

IN0

9

No LC sensor input

B

GND

10

No power supply to device

B

OUT3

11

Output is not connected to a load. May result in output status error

B

OUT2

12

Output is not connected to a load. May result in output status error

B

OUT1

13

Output is not connected to a load. May result in output status error

B

SDA

14

I2C read/write will be non-functional

B

OUT0

15

Output is not connected to a load. May result in output status error.

B

SCL

16

I2C read/write will be non-functional

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

COM

1

GND

COM is grounded without a bypass capacitor. Will cause an error in sensor input and unpredictable LC sensor behavior

B

GND

2

LPWRB

Device stuck in Low Power Mode

B

LPWRB

3

VDD

Device stuck in Normal Power Mode

B

VDD

4

INTB

INTB stuck high; loss of INTB functionality

B

INTB

5

IN3

Loss of INTB functionality

and error in sensor input

B

IN3

6

IN2

Error in LC sensor input

B

IN2

7

IN1

Error in LC sensor input

B

IN1

8

IN0

Error in LC sensor input

B

IN0

9

GND

No LC sensor input

B

GND

10

OUT3

May result in output status error

B

OUT3

11

OUT2

May result in output status error

B

OUT2

12

OUT1

May result in output status error

B

OUT1

13

SDA

May result in output status error

B

SDA

14

OUT0

I2C read/write will be non-functional

B

OUT0

15

SCL

May result in output status error and I2C read/write will be non-functional

B

SCL

16

COM

I2C read/write will be non-functional

B

Table 4-5 Pin FMA for Device Pins Short-Circuited to supply
Pin Name Pin No. Description of Potential Failure Effect(s) Failure Effect Class

COM

1

Will cause unpredictable LC sensor behavior

B

GND

2

Power supply shorted to ground

B

LPWRB

3

Device stuck in Normal Power Mode

B

VDD

4

Normal operation

D

INTB

5

Loss of INTB functionality

B

IN3

6

No LC sensor input

B

IN2

7

No LC sensor input

B

IN1

8

No LC sensor input

B

IN0

9

No LC sensor input

B

GND

10

Power supply shorted to ground

B

OUT3

11

Error in logic output

B

OUT2

12

Error in logic output

B

OUT1

13

Error in logic output

B

SDA

14

I2C read/write will be non-functional

B

OUT0

15

Error in logic output

B

SCL

16

I2C read/write will be non-functional

B