Functional Test Engineer (Experience in Debug)

Littelfuse; Piedras Negras; On-site; MXN 600,000 - 900,000; Full time

Job summary

Littelfuse is seeking a Functional Test Engineer to validate complex hardware and software systems, develop validation environments, and drive root-cause analysis across hardware, firmware and software teams.

You will build automation tools in Python and LabVIEW, triage failures, document processes in Jira and Git, and work with cross‑functional colleagues to ensure robust, market‑ready products. This role requires 10+ years of experience and a strong background in ASIC/SoC bring‑up.

Qualifications

• 10+ years of experience in system validation, functional testing, ASIC/SoC debug, or related engineering roles.
• Strong understanding of computer architecture, microprocessors, memory subsystems (DDR, PCIe), and communication protocols (I2C, SPI, UART, USB).
• Proficiency in scripting and automation languages such as Python, LabVIEW, or Ladder Logic.
• Working knowledge of C/C++ for firmware or driver‑level debugging.
• Experience with version control and bug tracking tools (Git, Jira, Bugzilla, or equivalent).
• Exceptional analytical and problem‑solving skills with a structured, investigative mindset.
• Strong communication skills, able to explain complex technical issues to both technical and non‑technical audiences.

Responsibilities

• Executes functional validation plans and test suites at system and subsystem levels under a variety of operating conditions.
• Acts as the first line of defense for system failures by isolating, reproducing, and debugging complex functional, performance, and power‑related issues.
• Performs deep‑dive root cause analysis to determine whether failures originate from hardware, software, firmware, or test environment issues.
• Develops and maintains automation scripts and tools (Python, LabView, etc.) to streamline test execution, data collection, and CI flows.
• Collaborates cross‑functionally with Hardware/ASIC Design, Firmware, Architecture, and Software teams to communicate findings, propose workarounds, and verify fixes.
• Documents debug methodologies, maintains detailed bug tracking records, and provides regular status updates to project stakeholders.
• Execute and triage complex system‑level validation scenarios, including performance, power, and functional coverage.
• Drive ownership of failure analysis from symptom to resolution, identifying cross‑domain interactions.
• Build and optimize validation tools, scripts, and infrastructure to improve efficiency and repeatability.
• Utilize lab equipment (oscilloscopes, logic analyzers, protocol analyzers, JTAG, PLC, DAC cards) and software debuggers (GDB, logging, tracing tools) as required.
• Partner closely with engineering teams to accelerate issue resolution and ensure design robustness.
• Maintain clear, structured documentation of bugs, test coverage, and debug processes using Jira, Git, or similar systems.

Skills

System validation

Functional testing

Debugging

Python scripting

LabVIEW

C/C++

Git/Jira

SoC bring-up

Test automation

Data analysis

Education

Bachelor's degree in Electrical/Computer Engineering

Tools

Oscilloscope

Logic analyzers

JTAG

Git

Jira

Bugzilla

CI pipelines

Job description

Littelfuse (NASDAQ: LFUS) is a diversified industrial technology manufacturing company shaping solutions for the safe and efficient transfer of electrical energy. Headquartered in Chicago, Illinois, USA, we serve customers across industrial, transportation, and electronics markets worldwide. With approximately 16,000 employees we design and manufacture innovative technologies that support electrification, energy efficiency, and advanced automation. Our global reach is matched by a culture that empowers innovation and long‑term growth. Guided by our principles We Care, We Succeed With Our Customers, and We Own the Outcome, we work collaboratively, think boldly, and deliver solutions that move industries forward. As a Functional Test Engineer (Experience in Debug), you will play a critical role in ensuring our products meet all architectural specifications and functional requirements. You will be responsible for creating validation environments, executing complex system‑level test plans, and performing deep root‑cause analysis on failures across hardware and software domains. You will work closely with design, architecture, firmware, and software teams to isolate defects, validate fixes, and ensure high‑quality products are delivered to market.

About Your Job:

• Executes functional validation plans and test suites at system and subsystem levels under a variety of operating conditions.
• Acts as the first line of defense for system failures by isolating, reproducing, and debugging complex functional, performance, and power‑related issues.
• Performs deep‑dive root cause analysis to determine whether failures originate from hardware, software, firmware, or test environment issues.
• Develops and maintains automation scripts and tools (Python, LabView, etc.) to streamline test execution, data collection, and CI flows.
• Collaborates cross‑functionally with Hardware/ASIC Design, Firmware, Architecture, and Software teams to communicate findings, propose workarounds, and verify fixes.
• Documents debug methodologies, maintains detailed bug tracking records, and provides regular status updates to project stakeholders.
• Execute and triage complex system‑level validation scenarios, including performance, power, and functional coverage.
• Drive ownership of failure analysis from symptom to resolution, identifying cross‑domain interactions.
• Build and optimize validation tools, scripts, and infrastructure to improve efficiency and repeatability.
• Utilize lab equipment (oscilloscopes, logic analyzers, protocol analyzers, JTAG, PLC, DAC cards) and software debuggers (GDB, logging, tracing tools) as required.
• Partner closely with engineering teams to accelerate issue resolution and ensure design robustness.
• Maintain clear, structured documentation of bugs, test coverage, and debug processes using Jira, Git, or similar systems.

About You:

• 10+ years of experience in system validation, functional testing, ASIC/SoC debug, or related engineering roles.
• Strong understanding of computer architecture, microprocessors, memory subsystems (DDR, PCIe), and communication protocols (I2C, SPI, UART, USB).
• Proficiency in scripting and automation languages such as Python, LabView, or Ladder Logic.
• Working knowledge of C/C++ for firmware or driver‑level debugging.
• Experience with version control and bug tracking tools (Git, Jira, Bugzilla, or equivalent).
• Exceptional analytical and problem‑solving skills with a structured, investigative mindset.
• Strong communication skills, able to explain complex technical issues to both technical and non‑technical audiences.
• Resilient, detail‑oriented, and persistent in highly iterative debug environments.
• Bachelor’s or Master’s degree in Electrical Engineering, Computer Engineering, Computer Science, or a related field (or equivalent experience).
• Hands‑on experience with ASIC or SoC bring‑up and post‑silicon validation.
• Exposure to CI pipelines and automated validation frameworks.
• Experience working in highly cross‑functional, global engineering teams.
• Strong documentation skills and ability to create repeatable debug playbooks.

Littelfuse is an equal opportunity employer committed to empowering every associate to make a difference — everywhere, every day.

#LI-KRL At Littelfuse, we support employee growth and development.

Guided by our culture principles, our teams work together to deliver value for customers and make a positive impact in the communities where we operate.

We are an equal opportunity employer committed to fostering an inclusive workplace where everyone has the opportunity to grow and contribute.

We offer competitive compensation and benefits, performance‑based incentives, flexible work arrangements, and development opportunities.

Our humble roots date back to 1927, where, in the back of a garage on Chicago’s northside, our founder, Edward Sundt, developed a small, fast‑acting, protective fuse for use in sensitive test meters. Sundt wanted to call his new company producing these small fuses, “Little Fuse,” but wasn’t allowed to trademark two such common words. So, instead he went with the one‑word, misspelled “Littelfuse.” For more than 95 years, Littelfuse has pioneered innovative products that help empower a sustainable, connected, and safer world. With the ever‑evolving electrification and electronification of customer applications, our product technologies are closely linked to sustainable applications such as electric vehicles and EV charging infrastructure, renewable energy and energy storage, factory automation, power management and more.

Throughout our history, our people have been the foundation of our success — and that remains true today. Now more than ever, our bright and talented people are a strategic advantage for the company. From the production line to the engineering lab, the office or distribution center, Littelfuse people are an important part of a diverse, talented team of the best and brightest in the industry. While Littelfuse has experienced tremendous growth in recent years, we still maintain a small‑company, entrepreneurial approach where your efforts will drive our culture, our business, and the overall success of the organization. No matter where you work or what you do, your contributions will make a difference at Littelfuse — everywhere, every day.

Littelfuse is an Equal Opportunity/Affirmative Action employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, gender identity, sexual orientation, disability, protected veteran status, and/or any other protected class under federal, state, or local law.