Semiconductor Testing Services

UL Solutions delivers semiconductor testing, reliability evaluation, performance validation and regulatory compliance services.

Semiconductor testing for isolated devices

Where these semiconductors are used
Our semiconductor testing focuses on electrically isolated semiconductor devices that protect circuits under fault conditions across demanding applications, from drives for motor control and welding systems to industrial heating, portable generators, power quality equipment, fast EV charging, solar inverters, wind turbines and battery energy storage.

Why UL Solutions for semiconductor test services
As a trusted semiconductor testing company, we work closely with your engineering teams to navigate requirements, promote safety and help you bring products to market quickly and efficiently, leveraging scientific expertise, objective authority and market access.

What we test and certify

Device categories we cover
UL Solutions provides testing and U.S. recognition for many semiconductor types, including electrically isolated semiconductor devices, power switching semiconductors, SOT‑XXX packaged devices and large power modules.

Ratings included in certification

Maximum ON-state current
A curve of ON-state or forward current versus case temperature; or a maximum case temperature
RMS isolation voltage
Maximum junction temperature
Maximum storage temperature
Isolation voltage plus case and storage temperature ratings, reflecting the isolation‑related safety attributes evaluated during testing.

How we help you reach your target markets

Early engagement and material evaluation
Engage with us early. We can help you build in compliance from the start.

Thermal aging and evidence review
Where needed, testing is straightforward and may include long‑term thermal aging. We collaborate on oven time/temperature choices aligned to your required temperature rating and can review your thermal scans or similar data to support efficient test planning.

Use your semiconductor test system under DAP
If you maintain in‑house capability, you may qualify to conduct testing at your facility through UL’s Data Acceptance Program (DAP), a route that can help reduce certification cost and time while UL reviews and audits submitted data for certification use.

Standards and evaluation scope

UL 1557 isolation performance
Testing addresses electric shock hazards and evaluates isolation performance to UL 1557, the Standard for Safety for Electrically Isolated Semiconductor Devices, covering electrically isolated semiconductor devices such as thyristors, transistors and diodes, including combinations in module packages and relevant construction features.

What’s out of scope
Switching performance is not covered under this evaluation.

Get started

Begin your semiconductor test project with our team to map standards, samples and timelines, and explore DAP eligibility if you plan to utilize your own semiconductor test system.

Which electrically isolated semiconductor devices qualify for UL 1557 evaluation?

UL 1557 applies to isolation performance for devices such as thyristors, transistors and diodes, including their combinations in module packages where isolation construction features are pertinent.

Does UL 1557 include switching performance tests?

No. The evaluation does not cover switching performance; it focuses on isolation and electric shock hazards.

What information helps accelerate a project at kickoff?

Engage early and share key design inputs, selected polymeric materials, intended temperature ratings and any thermal scans or similar data, so we can align construction reviews and aging plans before test execution.

Can we test at our facility using our own semiconductor test system?

Yes. Qualified manufacturers may test at their facilities under UL’s Data Acceptance Program (DAP). UL reassesses labs annually and reviews/audits data before it’s used for certification. This path can help reduce costs and time.

Can semiconductor testing be combined with EMC or functional safety evaluations?

Yes. Many teams add EMC testing to meet market requirements and leverage UL’s global EMC lab network and market access support; system‑level controls and functional safety services are also available for products embedding semiconductors.

Which application areas commonly drive requests for isolated semiconductor testing?

Typical use cases range from industrial drives, welding and heating to portable generators, power quality, fast EV charging, solar inverters, wind turbines and battery energy storage systems.

EMC testing and Global Market Access

Pair your semiconductor services with EMC testing to address electromagnetic requirements and streamline approvals. UL Solutions operates a global network of EMC laboratories and provides guidance across IEC and CISPR standards, with programs that support access to 150+ countries.

Home automation control station in a modern home

Controls and functional safety for semiconductor‑based systems

For products and systems embedding semiconductors (e.g., controls and drives), UL provides safety evaluations, functional safety assessments and broader compliance support across hardware and software, including ISO 26262‑related services.

Close up of a printed green computer circuit board

PCB safety and reliability

If you also need PCB safety compliance and reliability testing for designs supporting high‑frequency, high‑density applications, UL evaluates to UL, IEC, ASTM and IPC requirements, including thermal/environmental conditioning and interconnect stress testing.