SFFS006B November 2020 – March 2024 LMR33610 , LMR33620 , LMR33630 , LMR33640
4.1 VQFN Package
Figure 4-2 shows the LMR336x0 pin diagram for the VQFN package (RNX designator). For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the appropriate device data sheet.
Figure 4-1 Pin
DiagramTable 4-2 Pin FMA for Device Pins
Short-Circuited to Ground
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| PGND | 1,11 | No effect | D |
| VIN | 2,10 | Device will not operate. No output voltage will be generated. Output capacitors will discharge through input short. Large reverse current may damage device. | A |
| N/C | 3 | No effect if this pin is not used by customer. | D |
| When used to route the SW node to connect CBOOT (as recommended), damage to internal power FETs and other internal circuits. | A | ||
| BOOT | 4 | Damage to internal circuits | A |
| VCC | 5 | Fault mode will shut device off | B |
| AGND | 6 | No effect | D |
| FB | 7 | The regulator will operate at maximum duty cycle. Output voltage will rise to nearly the input voltage (VIN) level. Possible damage to customer load and output stage components may occur. No effect on device. | B |
| PG | 8 | Power good functionality will be lost. | B |
| EN | 9 | Loss of ENABLE functionality Device will remain in shutdown mode. | B |
| SW | 12 | Damage to internal power FETs and other internal circuits | A |
Table 4-3 Pin FMA for Device Pins
Open-Circuited
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| PGND | 1,11 | With either one or both pins open, possible device damage. | A |
| VIN | 2,10 | With both pins open, there can be loss of output voltage. With one pin open, there can be possible device damage. | A |
| N/C | 3 | No effect if this pin is not used by customer. | D |
| When used to route the SW node to connect CBOOT (as recommended), the effect is the same as open on pin 4. | B | ||
| BOOT | 4 | Loss of output voltage regulation; low or no output voltage. | B |
| VCC | 5 | VCC LDO will be unstable. Loss of output voltage regulation and possible damage to internal circuits. | A |
| AGND | 6 | Loss of output voltage regulation. Possible damage to internal circuits. | A |
| FB | 7 | Loss of output voltage regulation. Output voltage may rise or fall outside of intended regulation window. | B |
| PG | 8 | PG functionality will be lost. | B |
| EN | 9 | Loss of ENABLE functionality. Erratic operation; probable loss of regulation. | B |
| SW | 12 | Loss of output voltage. | 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 |
|---|---|---|---|---|
| PGND | 1 | VIN | Device will not operate. No output voltage will be generated. Output capacitors will discharge through input short. Large reverse current may damage device. | A |
| VIN | 2 | N/C | No effect if this pin is not used by customer. | D |
| When used to route the SW node to connect CBOOT (as recommended), the output voltage will rise to nearly the level of VIN. Customer load will be damaged. Possible damage to device | A | |||
| N/C | 3 | BOOT | No effect if this pin is not used by customer. | D |
| When used to route the SW node to connect CBOOT (as recommended), damage to internal circuits. No output voltage will be produced. | A | |||
| BOOT | 4 | VCC | Loss of output regulation, possible damage to internal circuits | A |
| VCC | 5 | AGND | Fault mode will shut device off | B |
| AGND | 6 | FB | The regulator will operate at maximum duty cycle. Output voltage will rise to nearly the input voltage (VIN) level. Possible damage to customer load and output stage components may occur. No effect on device. | B |
| FB | 7 | PG | Erratic operation; probable loss of regulation. Possible output voltage increase and damage to customer load. | B |
| PG | 8 | EN | Erratic operation; probable loss of regulation. | B |
| EN | 9 | VIN | This is a valid connection for the EN input. Enable functionality will be lost; the device will remain on. | B |
| VIN | 10 | PGND | Device will not operate. No output voltage will be generated. Output capacitors will discharge through input short. Large reverse current may damage device. | A |
| PGND | 11 | SW | Damage to internal power FETs and other internal circuits | A |
Table 4-5 Pin FMA for Device Pins
Short-Circuited to VIN
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| PGND | 1,11 | Device will not operate. No output voltage will be generated. Output capacitors will discharge through input short. Large reverse current may damage device. | A |
| VIN | 2,10 | No effect. | D |
| N/C | 3 | No effect if this pin is not used by customer. | D |
| When used to route the SW node to connect CBOOT (as recommended), the output voltage will rise to nearly the level of VIN. Customer load will be damaged. Possible damage to device | A | ||
| BOOT | 4 | Damage to internal circuits | A |
| VCC | 5 | Damage to internal circuits for VIN > 5.5V | A |
| AGND | 6 | Possible damage to internal circuits or package | A |
| FB | 7 | Damage to internal circuits will occur for VIN > 5.5V. | A |
| PG | 8 | Damage to internal circuits. | A |
| EN | 9 | No damage to device. Loss of ENABLE functionality. | B |
| SW | 12 | The output voltage will rise to approximately the level of VIN. Customer load will be damaged. Possible damage to device | A |