Roles they hire for
- HAL and peripheral driver engineer (MCX, i.MX RT, i.MX)
- Security ROM and firmware engineer
- Automotive MCU field applications engineer
What they emphasise
- HAL and drivers that run bare-metal, from ROM and under an RTOS
- Verifying ROM code on pre-silicon RTL and emulation platforms
- i.MX secure boot, crypto drivers and trusted execution environments
- ISO 26262 and AUTOSAR awareness in automotive roles
Brush up on
MCUXpresso SDKZephyrROM code constraintsPre-silicon validationSecure bootISO 26262AUTOSAR
How the rounds usually run
A typical silicon vendor loop for embedded roles. Companies vary by team and seniority.
Online assessment or screen
- C output prediction, pointers and bit manipulation
- Digital logic and OS basics
- For experienced hires, often a recruiter and hiring-manager screen instead
Example: What does this print: an unsigned char set to 200 plus 100, printed as an integer?
Technical 1: C and embedded fundamentals
- Pointers, volatile, const, alignment and endianness
- Interrupts, stacks and memory layout
- Live C coding on bit fields, ring buffers or string handling
Example: Implement a lock-free single-producer, single-consumer ring buffer.
Technical 2: Drivers and architecture
- Designing a peripheral driver and its API
- DMA, caches and interrupt priorities
- RTOS internals and debugging stories
Example: Design a SPI driver that supports blocking, interrupt and DMA modes behind one API.
Technical 3 or hiring manager: system design and projects
- Deep dive into a past project and your design choices
- System-level trade-offs: power, memory, performance
- Sometimes a short presentation on a project
Example: Walk through the hardest bug you've fixed, and what you changed in the process afterwards.
HR and behavioural
- Motivation, teamwork and conflict
- Relocation, notice period and compensation
Example: Tell me about a time you disagreed with a design decision.
Practice questions
Original questions written for NXP Semiconductors's focus areas, not leaked ones.
- Design a UART driver that ships in boot ROM and also in the SDK under an RTOS. What changes, and what must never change once the ROM is taped out?
- How would you test a peripheral driver before silicon exists?
- Describe a secure boot chain from ROM to application and what each stage verifies.
- A customer reports your SPI driver works at 10 MHz but fails at 40 MHz on their board. How do you triage it remotely?
- How would you design a driver API so the same code supports an I2C controller in both master and slave modes?
Your prep playlist
Design rounds to practise
Sources
Take an AI mock round styled on NXP Semiconductors, with follow-ups that probe what you missed.
Start a mock round