Embedded software engineer – Drives

Apply before: as soon as possible | Last updated: 09-09-2026 09:24:53

If you’re an experienced embedded software engineer who enjoys working where SOFTWARE, POWER ELECTRONICS, MOTOR TECHNOLOGY and CONTROL ENGINEERING meet, this could be the job for you.

OJ Electronics – a Danish producer of HVAC drives, AHU controllers, and thermostats for electric floor heating – is looking for an intermediate/senior-level embedded software engineer to join our Drives software team in Sønderborg, Denmark.

Your main job will be to develop the embedded software behind our VARIABLE SPEED DRIVES for energy-efficient HVAC applications – working on solutions that combine sophisticated control with robust, real-world performance.

You’ll be involved throughout the development process, from early ideas and system architecture to simulation, testing and validation. And because our products bring software and hardware closely together, you’ll work across disciplines rather than disappearing into a software silo.

Your role

Reporting directly to our R&D development manager, you’ll be expected to:

• Develop embedded software solutions, primarily for power electronics and variable speed drives
• Participate in cross-functional development projects
• Contribute during early ideation phases
• Solve complex development challenges
• Contribute to system design and architecture
• Build robust simulation models to validate control concepts early in the development cycle
• Take responsibility for documentation
• Participate in testing and validation
• Sometimes help customers directly with troubleshooting and issue resolution

Broad-based collaboration

As part of our diverse R&D team, you’ll work alongside hardware engineers and other specialists, contributing to the entire product lifecycle and getting involved in challenges ranging from communication and automation protocols to motor technologies and control-system engineering.

You’ll also have the satisfaction of seeing your own code running in thousands of products – helping improve everyday comfort and energy efficiency for users around the world.

Must-have qualifications

• A bachelor’s or master’s degree in embedded software, electronics engineering or a similar field
• At least three years of professional embedded software development experience
• Strong C/C++ skills for embedded systems
• Experience with microcontrollers and real-time programming
• Experience with motor control systems
• Understanding of control engineering in embedded systems
• Hands-on experience with hardware/software debugging tools such as oscilloscopes, logic analyzers, and JTAG
• A good understanding of hardware/software interfaces
• The ability to read and interpret schematics and datasheets
• Experience with Git, Git Flow and CI/CD
• Knowledge of communication interfaces such as UART, I2C and SPI
• Practical laboratory testing and validation experience
• Structured problem-solving and debugging skills
• Clear and concise technical communication in English
• A team-oriented mindset and experience with agile collaboration

Nice-to-have qualifications

Experience with:

• Modbus or BACnet
• MATLAB simulation
• Wi-Fi or Bluetooth Low Energy
• Embedded-system security

Working at OJ

At OJ Electronics, you’ll find an informal, open and collaborative culture where people take pride in doing quality work.

We offer:

• A flat organizational structure where decisions are made quickly
• Opportunities to grow your expertise and responsibility over time
• A healthy work-life balance and flexible working hours
• Competitive salary and pension package
• A modern workplace with canteen and good facilities

Employee satisfaction scores average 85 – and we take pride in maintaining a workplace where people truly thrive.

Please note that this position is based in Sønderborg, Denmark, and requires your physical presence on site. This is not a hybrid or remote position.

The application process

For this position, we will be interviewing on an ongoing basis until we find the right person.

About OJ Electronics

Founded in 1964 and headquartered in Sønderborg, Denmark, OJ Electronics produces electronic controls for underfloor heating and HVAC controls and drives. Our products are available through partners and distributors worldwide, and we have subsidiaries and sales offices in key markets, including the United States and Poland. Everywhere, we are known for our innovative approach, insistence on product quality, and deep application knowledge – all of which helps customers differentiate themselves in the market.

In June 2023, OJ Electronics was acquired by BITZER Electronics, a BITZER Group company also headquartered in Sønderborg. This makes OJ Electronics part of the BITZER Group family, which is represented at 75 locations in over 40 countries and employs some 4300 people worldwide, 185 in OJ Electronics, Sønderborg, Denmark.

Contact

Ken Rønnow

R&D Manager

Mail: ker@ojelectronics.com

Mobile: 30546598