SFFS115 March 2021 DRV8889-Q1

2 Functional Safety Failure In Time (FIT) Rates

This section provides Functional Safety Failure In Time (FIT) rates for DRV8889-Q1 and DRV8889A-Q1 based on two different industry-wide used reliability standards:

Table 2-1 provides FIT rates based on IEC TR 62380 / ISO 26262 part 11 for the HTSSOP Package.
Table 2-2 provides FIT rates based on IEC TR 62380 / ISO 26262 part 11 for the QFN Package.
Table 2-3 provides FIT rates based on the Siemens Norm SN 29500-2.

Table 2-1 Component Failure Rates per IEC TR 62380 / ISO 26262 Part 11 for HTSSOP Package

FIT IEC TR 62380 / ISO 26262	FIT (Failures Per 10⁹ Hours)
Total Component FIT Rate	23
Die FIT Rate	7
Package FIT Rate	16

Table 2-2 Component Failure Rates per IEC TR 62380 / ISO 26262 Part 11 for QFN Package

FIT IEC TR 62380 / ISO 26262	FIT (Failures Per 10⁹ Hours)
Total Component FIT Rate	21
Die FIT Rate	9
Package FIT Rate	12

The failure rate and mission profile information in Table 2-1 and Table 2-2 comes from the Reliability data handbook IEC TR 62380 / ISO 26262 part 11:

Mission Profile: Motor Control from Table 11
Power dissipation: 1 W
Climate type: World-wide Table 8
Package factor (lambda 3): Table 17b
Substrate Material: FR4
EOS FIT rate assumed: 0 FIT

Table 2-3 Component Failure Rates per Siemens Norm SN 29500-2

Table	Category	Lambda ref FIT	Theta vj
5	CMOS/BICMOS ASICs Analog & Mixed =<50V supply	60 FIT	70°C

The Reference FIT Rate and Reference Virtual T_J (junction temperature) in Table 2-3 come from the Siemens Norm SN 29500-2 tables 1 through 5. Failure rates under operating conditions are calculated from the reference failure rate and virtual junction temperature using conversion information in SN 29500-2 section 4.