SLVAEK2A December 2019 – December 2020 TPS2H160-Q1
4 Pin Failure Mode Analysis (Pin FMA)
This section provides a Failure Mode Analysis (FMA) for the pins of the TPS2H160-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
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
| 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 TPS2H160-Q1 pin diagram. For a detailed description of the device pins please refer to the Pin Configuration and Functions section in the TPS2H160-Q1 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 |
|---|---|---|---|
| INx | 1,2 | Shutdown of corresponding channel | B |
| DIAG_EN | 3 | Diagnostics will be disabled | B |
| NC | 4,10 | Pin 4 is NC for Version A only. No effect | D |
| FAULT | 4 | Version B only: Fault status reported may be erroneous | B |
| STx | 5,6 | Version A only: Status being reported may be erroneous | B |
| SEL | 5 | Version B only: If DIAG_EN is high then channel 1's sense current output always on SNS | B |
| CS | 6 | Version B only: Sense current not valid from CS pin | B |
| CL | 7 | Device will default to internal current limit | C |
| GND | 8 | Resistor/diode network will be bypassed if present | B |
| THER | 9 | Device will default to "auto-retry" mode when encountering thermal fault | B |
| OUTx | 11,12,15,16 | Current limit of device will engage | B |
| VS | 13,14 | Device will have no input supply and therefore not function | B |
Table 4-3 Pin FMA for Device Pins
Open-Circuited
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| INx | 1,2 | Corresponding channel will be shutdown and INx will be pulled down internally | B |
| DIAG_EN | 3 | Diagnostics will be disabled with device as pin will be pulled down internally | B |
| NC | 4,10 | Pin 4 is NC for Version A only. No effect | D |
| FAULT | 4 | Version B only: Fault signal not reported | B |
| STx | 5,6 | Version A only: STx pin cannot pull high and diagnostics cannot be reported | B |
| SEL | 5 | Version B only: Pin pulled low internally, however wrong SNS current potentially reported on CS if DIAG_EN is high | B |
| CS | 6 | Correct CS current cannot be read | B |
| CL | 7 | Channel 1 and 2 will not be able to provide output current | B |
| GND | 8 | Loss of ground detection engages and device shuts off | B |
| THER | 9 | Internally pulled down and device will default to "auto-retry" mode when encountering thermal fault | B |
| OUTx | 11,12,15,16 | No effect. If configured, open load detection will trigger | B |
| VS | 13,14 | Device will have no input supply and therefore not function | 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 |
|---|---|---|---|---|
| IN1 | 1 | IN2 | IN1 signal will affect IN2 signal and vice versa | B |
| IN2 | 2 | DIAG_EN | IN2 signal will affect DIAG_EN signal and vice versa | B |
| DIAG_EN | 3 | NC | Version A only. No effect | D |
| DIAG_EN | 3 | FAULT | Version B only. Signal of DIAG_EN could affect FAULT signal and vice versa | B |
| NC | 4 | ST1 | Version A only. No effect | D |
| FAULT | 4 | SEL | Version B only. FAULT status could affect SEL signal and vice versa | B |
| ST1 | 5 | ST2 | Version A only. False ST1 status could be reported on ST2 and vice versa | B |
| SEL | 5 | CS | Version B only. Signal on SEL could affect signal on CS pin and vice versa | B |
| ST2 | 6 | CL | Version A only. If ST2 is high then and channel 1 and channel 2 will not be able to provide output current. If ST2 is low the internal current limit will be set | B |
| CS | 6 | CL | Version B only. Voltage level on CS could cause erroneous current limit to be set on device | B |
| CL | 7 | GND | Device will default to internal current limit | B |
| THER | 9 | NC | No effect | D |
| NC | 10 | OUT2 | No effect | D |
| OUT2 | 11 | OUT2 | No effect | D |
| VS | 13 | VS | No effect | D |
| VSx | 12,15 | VOUTx | Output will be pulled supply voltage. Short-to-battery detection will be triggered if configured | B |
| OUT1 | 15 | OUT1 | No effect | D |
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 |
|---|---|---|---|
| INx | 1,2 | Potential violation of absolute maximum rating of pin and possible breakdown of ESD cell | A |
| DIAG_EN | 3 | Potential violation of absolute maximum rating of pin and possible breakdown of ESD cell | A |
| NC | 4,10 | Pin 4 is NC on Version A only. Pins not internally connected | D |
| FAULT | 4 | Version B only. Potential violation of absolute maximum rating of pin and possible breakdown of ESD cell | A |
| SEL | 5 | Version B only. Potential violation of absolute maximum rating of pin and possible breakdown of ESD cell | A |
| STx | 5,6 | Version A only: Potential violation of absolute maximum rating of pin and possible breakdown of ESD cell | A |
| CS | 6 | Version B only: Potential violation of absolute maximum rating of pin and possible breakdown of ESD cell | A |
| CL | 7 | Potential violation of absolute maximum rating of pin and possible breakdown of ESD cell | A |
| GND | 8 | Supply power will be bypassed and device will not turn on | B |
| THER | 9 | Potential violation of absolute maximum rating of pin and possible breakdown of ESD cell | A |
| OUTx | 11,12,15,16 | Output will be pulled supply voltage. Short-to-battery detection will be triggered if configured | B |