Key takeaways
AEC-Q and ISO 16750 validate two different levels. AEC-Q100/101/104/200 cover accelerated life and failure criteria for chips, PCBs and passive parts; ISO 16750 covers the environment an assembly sees once installed. An automotive-grade part is the foundation of assembly reliability, but vehicle-level vibration, temperature and electrical loads still have to be validated to the assembly standard. OEM supplier audits normally ask for both.
"We use automotive-grade parts, so do we still need 16750?" Suppliers ask this a lot. The answer up front: yes. AEC-Q and ISO 16750 do not validate the same object, and passing the first does not mean passing the second.
1. The two standards validate different objects
AEC-Q addresses the component itself: Q100 for integrated circuits, Q101 for discrete semiconductors, Q104 for multi-chip modules, Q200 for passive components. It answers "how does this part behave under accelerated stress", and gives components a common set of stresses and acceptance criteria.
ISO 16750 addresses the assembly as installed: the vibration profile comes from the mounting position, the temperature from the vehicle's climate zone, the electrical loads from the vehicle power supply. It answers "can this assembly survive its design life in this position on the vehicle".
2. Why one cannot replace the other
Automotive-grade components set a floor on the part itself, but assembly failures usually happen at system level: solder joints fatigue under the vehicle vibration profile, connector contact resistance drifts, housing seals fail in salt spray — none of which appear in the AEC-Q stress conditions. Conversely, an assembly that passes 16750 does not prove every part inside carries Q qualification.
3. How they work together in practice
- Selection: for critical devices (MCU, power devices, MOSFETs) prefer part numbers backed by AEC-Q reports, and ask the supplier for them
- Design: derive the assembly's vibration and temperature conditions from the mounting position, and keep derating margin
- Validation: run vehicle-level tests on the assembly to ISO 16750 / GB/T 28046 or the customer specification; add failure analysis on critical solder joints and interfaces where needed
- Iteration: a part change, a solder paste change or a structural change all need re-assessment — do not assume "it is the same"
4. Advice for purchasing and quality
Keep the component Q-qualification list and the assembly environmental test report as two separate files, and pull them separately during an OEM audit. Submit only one and you will be asked for the other.
Turnaround time is arranged according to the actual project. You are welcome to state your target date when submitting samples; we will check it against the current schedule, confirm a feasible plan with you, and update you at each milestone.
