ALTER TECHNOLOGY is proud to announce that we have been awarded the ESA contract AO/1-11032/24/NL/VR for the project titled “Reliability of Non-Hermetic Optocouplers for High Voltage Applications.” This initiative, part of ESA’s Technology Development Element (TDE), aims to assess the suitability of commercial high voltage optocouplers for future space missions, particularly in the context of New Space platforms where cost-effective, high-performance solutions are increasingly in demand.
In particular, the following key aspects have been considered:
1. Target of this ITT means commercial non hermetic optocouplers with the following ain characteristics:
- High output voltage optocoupler 100V ≤ VCE ≤ 400V and/or
- High insulation voltage 5kV ≤ VISO ≤ 15kV
2. Testing approach is devoted to characterization and understanding of potential degradation of main parameters with specific attention to thermal vacuum, humidity, endurance and radiation as main environmental effects.
3. Special attention has been given to the proposed test, and hence,e adequacy to ensure full testability of the parameters.
Commercial + HV optocouplers. A raising need.
High voltage optocouplers are critical components in spacecraft systems such as electric propulsion and solar arrays, where electrical isolation and signal integrity must be maintained under extreme environmental conditions. Traditionally, hermetic packages have been preferred for their robustness and widely tested by ALTER in previous missions like Solar Orbiter or JUICE, but the growing interest in COTS (Commercial Off-The-Shelf) components has opened new possibilities, provided their reliability can be demonstrated.
Figure 1: Example of HV optocoupler selected
This project addresses a key challenge: Can non-hermetic, commercially available optocouplers meet the stringent requirements of space environments, including radiation, vacuum, and thermal extremes?
Download slide deck with ALTER’s premises for optical testing
Our Approach: From Market Survey to Radiation Testing
ALTER has leveraged its 35+ years of experience in EEE parts procurement, testing, and qualification to conduct a comprehensive market survey. Over 90 optocoupler types were initially reviewed, with 23 shortlisted and 10 final candidates selected based on:
- Collector-emitter voltage (VCE) and insulation voltage (VISO) compliance
- Availability of reliability and radiation data
- Manufacturer cooperation and lead time
- European sourcing preference (when feasible)
The sequence agreed with ESA for the reliability testing includes outgassing evaluation, electrical characterization under vacuum and Nitrogen, 500/600 Thermal Cycles, Extensive life test and Temperature Humidity Biased testing. In addition, a key milestone will be initial radiation testing in terms of TID, TNID and SEE (transients have been demonstrated to be essential) on all the final 10 candidates.
Figure 2: List of test activities ALTER to be perform on the 10 candidates
Radiation Testing at CERN with RADNEXT and HEARTS
A major milestone in this project is ALTER’s successful application for beam time at CERN through the RADNEXT program. We will perform radiation testing at the HEARTS (High-Energy Accelerators for Radiation Testing and Shielding) facility, a cutting-edge infrastructure that enables Single Event Effect (SEE) testing without the need to delid components, preserving their optical functionality.
What is HEARTS?
HEARTS is a European initiative that provides access to high-energy heavy ion beams for radiation effects testing. Its capabilities allow for testing of packaged components under realistic conditions, avoiding the limitations of traditional lower-energy SEE facilities.
This collaboration with CERN and RADNEXT underscores ALTER’s commitment to using the most advanced facilities available to validate component performance in space-like environments.
ALTER’s Role in Space Radiation Engineering
This project is a continuation of ALTER TECHNOLOGY’s leadership in the field of radiation effects on EEE components. Our capabilities span:
- Radiation environment definition and simulation
- Total Ionizing Dose (TID), Displacement Damage (DD), and SEE testing
- Custom test setups for vacuum, thermal, and high-voltage conditions
- Virtual Lab® platform for real-time test monitoring and data management
We have previously supported ESA missions such as JUICE and Solar Orbiter, and this new contract further strengthens our position as a trusted partner in space component reliability.
Looking Ahead
The results of this evaluation campaign will provide ESA and the wider space community with critical insights into the use of non-hermetic HV optocouplers in future missions.
Stay tuned for updates as we move into the testing phase and share our findings with the community.
We would like to thank Florian Moliere (ESA) for his proactive contributions and collaboration in the development of these activities.
Manuel Morales Domínguez
Manuel has over 15 years of experience in the space industry, specialising in EEE components engineering. He has been involved in a wide range of international projects, with a strong focus on European space missions such as JUICE, Euclid, MTG, and BepiColombo. Deeply interested in emerging technologies, he explores their compatibility with both traditional and NewSpace business models.
Co-author: Miguel Ballesteros Delgado – Radiation Engineer at ALTER
