SFFS456 December 2025 TPS785-Q1
4.1 VSON Package
Figure 4-1 shows the TPS785-Q1 pin diagram for the VSON package with a fixed output. Figure 4-2 shows the TPS785-Q1 pin diagram for the VSON package with an adjustable output. For a detailed description of the device pins, see the Pin Configuration and Functions section in the TPS785-Q1 datasheet.
Figure 4-1 Pin Diagram (VSON Package), Fixed Version 
Figure 4-2 Pin Diagram (VSON Package), Adjustable VersionTable 4-2 Pin FMA for Device Pins
Short-Circuited to Ground
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| OUT | 1 | The device hits the current limit state. If power dissipation is significant, the device hits the thermal shutdown state. If the fault condition is not removed, the device can continue to cycle in and out of thermal shutdown. Continuously running the device above the rated current degrades the reliability of the device. | B |
| NC | 2 | NC Pin (Fixed Output): There is no impact to the device. The device operates as normal with improved thermal performance. | D |
| FB | FB Pin (Adjustable Output): The output voltage is not regulated. The device operates as a switch and VOUT tracks VIN. | B | |
| NC | 3 | There is no impact to the device. The device operates as normal with improved thermal performance. | D |
| NC | 4 | There is no impact to the device. The device operates as normal with improved thermal performance. | D |
| GND | 5 | There is no impact to the device. The device operates as normal. | D |
| NC | 6 | NC Pin (Regular Version): There is no impact to the device. The device operates as normal with improved thermal performance. | D |
| EN | 7 | EN Pin (Regular Version): The device remains in a disabled state. | B |
| IN | 8 | The output voltage is not regulated and remains low at 0V. | B |
Table 4-3 Pin FMA for Device Pins
Open-Circuited
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| OUT | 1 | The device output voltage is pulled to GND and the downstream devices do not receive power. | B |
| NC | 2 | NC Pin (Fixed Output): There is no impact to the device. The device operates as normal. | D |
| FB | FB Pin (Adjustable Output): The feedback loop is open, as a result, the output voltage is not regulated and remains in an indeterminate state. VOUT is potentially pulled down to GND. | B | |
| NC | 3 | There is no impact to the device. The device operates as normal. | D |
| NC | 4 | There is no impact to the device. The device operates as normal. | D |
| GND | 5 | With the reference pin floating, the voltages at the remaining pins are floating as well and the device is not functional. There is a risk of violating absolute maximum ratings. | B |
| NC | 6 | NC Pin (Regular Version): There is no impact to the device. The device operates as normal. | D |
| EN | 7 | EN Pin (Regular Version): The output voltage remains in an indeterminate state. | B |
| IN | 8 | There is no input to the LDO. The output voltage is not regulated. | B |
Table 4-4 Pin FMA for Device Pins
Short-Circuited to Adjacent Pin
| Pin Name | Pin No. | Shorted to | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|---|
| OUT | 1 | NC (pin 2) | (Fixed output.) There is no effect on
the device. The device operates as normal. (Adjustable output.) The output voltage is set to the internal reference voltage. |
D |
| FB (pin 2) | B | |||
| FB | 2 | NC (pin 3) | There is no effect on the device. The device operates as normal. | D |
| NC | 3 | NC (pin 4) | There is no effect on the device. The device operates as normal. | D |
| GND | 5 | NC (pin 6) | There is no effect on the device. The device operates as normal. | D |
| NC | 6 | EN (pin 7) | There is no effect on the device. The device operates as normal. | D |
| EN | 7 | IN (pin 8) | The device is always enabled. The peripherals connected to the EN pin are at risk of EOS. | B |
Table 4-5 Pin FMA for Device Pins Short-Circuited to
Supply
| Pin Name | Pin No. | Description of Potential Failure Effects | Failure Effect Class |
|---|---|---|---|
| OUT | 1 | The device does not regulate. | B |
| NC | 2 | (Fixed output.) There is no effect on the device. The device operates as normal. | D |
| FB | (Adjustable output.) The absolute maximum rating for the FB pin (2V max) can be violated, resulting in the device being destroyed. If the absolute maximum rating is not violated, the error amplifier closes the channel and there is no output voltage. | A | |
| NC | 3 | There is no effect on the device. The device operates as normal. | D |
| NC | 4 | There is no effect on the device. The device operates as normal. | D |
| GND | 5 | There is no output voltage. The performance of the system depends on upstream overcurrent protection. | B |
| NC | 6 | There is no effect on the device. The device operates as normal. | D |
| EN | 7 | The device is always enabled. | B |
| IN | 8 | There is no effect on the device. The device operates as normal. | D |