SLVAEV6 December 2020 DRV8702-Q1
4 Pin Failure Mode Analysis (Pin FMA)
This section provides a Failure Mode Analysis (FMA) for the pins of the DRV8702-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)
These PIN FMA tables 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 |
Figure 4-1 shows the DRV8702-Q1 pin diagram. For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the DRV8702-Q1 data sheet.
Figure 4-1 Pin DiagramFollowing are the assumptions of use and the device configuration assumed for the pin FMA in this section:
-
The device is used with external components consistent with the values described in the external component table of the datasheet.
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 |
|---|---|---|---|
| GND | 1 | Intended operation | D |
| IN1/PH | 2 | Gate driver input control stuck low. Driver output may not match input. | B |
| IN2/EN | 3 | Gate driver input control stuck low. Driver output may not match input. | B |
| GND | 4 | Intended operation | D |
| IDRIVE | 5 | Device IDRIVE setting potentially incorrect | B |
| VDS | 6 | Device VDS setting potentially incorrect | B |
| GND | 7 | Intended operation | D |
| nSLEEP | 8 | Device stuck in sleep state. Outputs non-operational. | B |
| GND | 9 | Intended operation | D |
| nFAULT | 10 | Device fault output indicator always active. | B |
| MODE | 11 | Device MODE setting potentially incorrect. | B |
| DVDD | 12 | Device external digital power supply stuck low. Device non-operational. | B |
| GND | 13 | Intended operation | D |
| AVDD | 14 | Device non-operational. Power dissipation through AVDD | B |
| VREF | 15 | Current limit will trip every cycle | B |
| SO | 16 | Device current sense feedback invalid. | B |
| GND | 17 | Intended operation | D |
| GH1 | 18 | HS1 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| SH1 | 19 | HS1 MOSFET non-functional. Device will report VDS fault | B |
| GL1 | 20 | LS1 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| SP | 21 | Device current sense feedback invalid. | B |
| SN | 22 | Device current sense feedback invalid. | B |
| SL2 | 23 | Sense amplifier output is always low, no current regulation | B |
| GL2 | 24 | LS2 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| SH2 | 25 | HS2 MOSFET non-functional. Device will report VDS fault | B |
| GH2 | 26 | HS2 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| VDRAIN | 27 | Device overcurrent monitors and open load diagnostic non-operational. | B |
| PVDD | 28 | Device external power supply stuck low. Device gate drivers and shunt amplifier non-operational. | B |
| VCP | 29 | Device will be damaged | A |
| CPH | 30 | Device will be damaged | A |
| CPL | 31 | Device will report a charge pump fault | A |
| NC | 32 | No effect | B |
Table 4-3 Pin FMA for Device Pins Open-Circuited
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| GND | 1 | Device behavior undefined, may retain operation due to alternative GND pin. | C |
| IN1/PH | 2 | Gate driver input control missing. Driver output may not match input. | B |
| IN2/EN | 3 | Gate driver input control missing. Driver output may not match input. | B |
| GND | 4 | Device behavior undefined, may retain operation due to alternative GND pin. | C |
| IDRIVE | 5 | Device IDRIVE setting potentially incorrect | B |
| VDS | 6 | Device VDS setting potentially incorrect | B |
| GND | 7 | Device behavior undefined, may retain operation due to alternative GND pin. | C |
| nSLEEP | 8 | Device stuck in sleep state. Outputs non-operational. | B |
| GND | 9 | Device behavior undefined, may retain operation due to alternative GND pin. | C |
| nFAULT | 10 | Device fault output indicator invalid. | B |
| MODE | 11 | Device MODE setting potentially incorrect. | B |
| DVDD | 12 | Device external digital power supply missing. Device non-operational. | B |
| GND | 13 | Device behavior undefined, may retain operation due to alternative GND pin. | C |
| AVDD | 14 | Device behavior undefined, regulator may not be stable. | B |
| VREF | 15 | Current limit will be unstable | B |
| SO | 16 | Device current sense feedback invalid. | B |
| GND | 17 | Device behavior undefined, may retain operation due to alternative GND pin. | C |
| GH1 | 18 | HS1 MOSFET off | B |
| SH1 | 19 | HS1 MOSFET non-functional, Device will report VDS fault | B |
| GL1 | 20 | LS1 MOSFET off | B |
| SP | 21 | Device current sense feedback invalid. | B |
| SN | 22 | Device current sense feedback invalid. | B |
| SL2 | 23 | Device will report a VDS fault | B |
| GL2 | 24 | LS2 MOSFET off | B |
| SH2 | 25 | HS2 MOSFET non-functional, Device will report VDS fault | B |
| GH2 | 26 | HS2 MOSFET off | B |
| VDRAIN | 27 | Device overcurrent monitors and open load diagnostic non-operational. | B |
| PVDD | 28 | Device external power supply missing. Device gate drivers and shunt amplifier non-operational. | B |
| VCP | 29 | Charge pump undervoltage and gate drivers disabled. | B |
| CPH | 30 | Charge pump undervoltage and gate drivers disabled. | B |
| CPL | 31 | Charge pump undervoltage and gate drivers disabled. | B |
| NC | 32 | Intended operation | 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 |
|---|---|---|---|---|
| GND | 1 | 2 | Logic operation is changed. Driver output may not match input. | B |
| IN1/PH | 2 | 3 | Logic operation is changed. Driver output may not match input. | B |
| IN2/EN | 3 | 4 | Logic operation is changed. Driver output may not match input. | B |
| GND | 4 | 5 | Increased switching losses in FETs or gate drive fault | B |
| IDRIVE | 5 | 6 | Device IDRIVE and VDS setting potentially incorrect | B |
| VDS | 6 | 7 | Device VDS setting potentially incorrect | B |
| GND | 7 | 8 | Device stuck in sleep state. Outputs non-operational. | B |
| nSLEEP | 8 | 9 | Device stuck in sleep state. Outputs non-operational. | B |
| GND | 9 | 10 | Device fault output indicator always active. | B |
| nFAULT | 10 | 11 | MODE will change to PH/EN whenever a FAULT occurs and nSLEEP toggled | B |
| MODE | 11 | 12 | Device MODE setting potentially incorrect. | B |
| DVDD | 12 | 13 | Device external digital power supply missing. Device non-operational. | B |
| GND | 13 | 14 | Device non-operational. Power dissipation through AVDD | B |
| AVDD | 14 | 15 | Current regulation disabled | B |
| VREF | 15 | 16 | Device current sense feedback invalid. | B |
| SO | 16 | 17 | Device current sense feedback invalid. | B |
| GND | 17 | 18 | HS1 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| GH1 | 18 | 19 | HS1 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| SH1 | 19 | 20 | GL1 output invalid, may violate GL1 abs max. | A |
| GL1 | 20 | 21 | LS1 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| SP | 21 | 22 | Device current sense feedback invalid. | B |
| SN | 22 | 23 | Device current sense feedback invalid. | B |
| SL2 | 23 | 24 | LS2 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| GL2 | 24 | 25 | GL2 output invalid, may violate GL2 abs max. | A |
| SH2 | 25 | 26 | HS2 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| GH2 | 26 | 27 | HS2 MOSFET off, energy limited by TDRIVE. Device will report VGS fault | B |
| VDRAIN | 27 | 28 | Hard short instead of a kelvin connection may degrate VDS accuracy | B |
| PVDD | 28 | 29 | Device will report a charge pump fault | A |
| VCP | 29 | 30 | Device will not power up | A |
| CPH | 30 | 31 | Device will report a charge pump fault | A |
| CPL | 31 | 32 | No effect | B |
| NC | 32 | 1 | No effect | B |