SFFS298 December 2021 AMC1300B-Q1
4 Pin Failure Mode Analysis (Pin FMA)
This section provides a failure mode analysis (FMA) for the pins of the AMC1300B-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
| 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 AMC1300B-Q1 pin diagram. For a detailed description of the device pins see the Pin Configuration and Functions section in the AMC1300B-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:
- Differential RC filter between INP and INN.
The series resistors are sized to limit the input currents into INP and INN to <10 mA in all circumstances (for example, if the device is unpowered and the input signal is applied). - INN is connected to GND1 through the filter resistor.
- For pins on high side:
Short-circuited to ground means short to GND1.
Short-circuited to supply means short to VDD1. - For pins on low side:
Short-circuited to ground means short to GND2.
Short-circuited to supply means short to VDD2.
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 |
|---|---|---|---|
| VDD1 | 1 | Device high side unpowered. Fail-safe output (see data sheet for more details). | B |
| INP | 2 | INP stuck low (GND1). Differential output (VOUTP – VOUTN) = –VINN x 8.2 with common-mode voltage approximately 1.44 V. | B |
| INN | 3 | INN stuck low (GND1). Differential output (VOUTP – VOUTN) = VINP x 8.2 with common-mode voltage approximately 1.44 V. | D |
| GND1 | 4 | No effect. Normal operation. | D |
| GND2 | 5 | No effect. Normal operation. | D |
| OUTN | 6 | OUTN stuck low (GND2). Excess current consumption from VDD2 source. Device damage plausible if condition is present for extended period of time. | A |
| OUTP | 7 | OUTP stuck low (GND2). Excess current consumption from VDD2. Device damage plausible if condition is present for extended period of time. | A |
| VDD2 | 8 | Device low side unpowered. OUTP and OUTN pins are driven to GND2. | B |
Table 4-3 Pin FMA for Device Pins
Open-Circuited
| Pin Name | Pin No. | Description of Potential Failure Effect(s) | Failure Effect Class |
|---|---|---|---|
| VDD1 | 1 | Device high side unpowered. Fail-safe output (see data sheet for more details). | B |
| INP | 2 | Differential output (VOUTP – VOUTN) undetermined, but with tendency to output +FS. | B |
| INN | 3 | Differential output (VOUTP – VOUTN) undetermined. | B |
| GND1 | 4 | Device high side unpowered. Fail-safe output (see data sheet for more details). | B |
| GND2 | 5 | Device behavior undetermined. VOUTN and VOUTP undetermined. | B |
| OUTN | 6 | Differential output (VOUTP – VOUTN) undetermined. | B |
| OUTP | 7 | Differential output (VOUTP – VOUTN) undetermined. | B |
| VDD2 | 8 | Device low side unpowered. VOUTN and VOUTP undetermined. | 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 |
|---|---|---|---|---|
| VDD1 | 1 | INP | INP stuck high (VDD1). In case VCM < VCMov, differential output (VOUTP – VOUTN) = +FS. In case VCM ≥ VCMov, fail-safe output (see data sheet for more details). | B |
| INP | 2 | INN | Differential input shorted. Differential output (VOUTP – VOUTN) = 0 V | B |
| INN | 3 | GND1 | INN stuck low (GND1). Differential output (VOUTP – VOUTN) = VINP × 8.2 with common-mode voltage approximately 1.44 V. | D |
| GND1 | 4 | GND2 | Not considered. Corner pin. | D |
| GND2 | 5 | OUTN | OUTN stuck low (GND2). Excess current consumption from VDD2 source. Device damage plausible if condition is present for extended period of time. | A |
| OUTN | 6 | OUTP | Differential output (VOUTP – VOUTN) = 0 V with common-mode voltage approximately 1.44 V. Excess current consumption from VDD2 source. Device damage plausible if condition is present for extended period of time. | A |
| OUTP | 7 | VDD2 | OUTP stuck high (VDD2). Excess current consumption from VDD2 source. Device damage plausible if condition is present for extended period of time. | A |
| VDD2 | 8 | VDD1 | Not considered. Corner pin. | 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 |
|---|---|---|---|
| VDD1 | 1 | No effect. Normal operation. | D |
| INP | 2 | INP stuck high (VDD1). In case VCM < VCMov, differential output (VOUTP – VOUTN) = +FS. In case VCM ≥ VCMov, fail-safe output (see data sheet for more details). | B |
| INN | 3 | INN stuck high (VDD1). In case VCM < VCMov, differential output (VOUTP – VOUTN) incorrect. In case VCM ≥ VCMov, fail-safe output (see data sheet for more details). | B |
| GND1 | 4 | Device high side unpowered. Fail-safe output (see data sheet for more details). | B |
| GND2 | 5 | Device low side unpowered. OUTP and OUTN pins are driven to GND2. | B |
| OUTN | 6 | OUTN stuck high (VDD2). Excess current consumption from VDD2 source. Device damage plausible if condition is present for extended period of time. | A |
| OUTP | 7 | OUTP stuck high (VDD2). Excess current consumption from VDD2 source. Device damage plausible if condition is present for extended period of time. | A |
| VDD2 | 8 | No effect. Normal operation. | D |