SFFS780 February   2024 TUSB4020BI-Q1

 

  1.   1
  2.   Trademarks
  3. 1Overview
  4. 2Functional Safety Failure In Time (FIT) Rates
  5. 3Failure Mode Distribution (FMD)
  6. 4Pin Failure Mode Analysis (Pin FMA)

3 Failure Mode Distribution (FMD)

The failure mode distribution estimation for the TUSB4020BI-Q1 in Table 3-1 comes from the combination of common failure modes listed in standards such as IEC 61508 and ISO 26262, the ratio of sub-circuit function size and complexity, and from best engineering judgment.

The failure modes listed in this section reflect random failure events and do not include failures resulting from misuse or overstress.

Table 3-1 Die Failure Modes and Distribution
Outputs of the TUSB4020BI-Q1 Function Die Failure Modes Failure Mode Distribution (%)
USB2 Upstream Communication Upstream communication error 18
USB Downstream 1 Communication Downstream 1 communication error 18
USB Downstream 2 Communication Downstream 2 communication error 18
Both USB Downstream 1 and 2 Communication Both downstream 1 and 2 communication error 2
USB Downstream 1 Charging control Downstream 1 charging error 14
USB Downstream 2 Charging control Downstream 2 charging error 14
Both USB Downstream 1 and 2 Charging control Both downstream 1 and 2 charging error 2
I2C/SMBus Communication I2C/SMBus control communication error 14