Taipei, Taiwan – November 19, 2025 – The delivery of 16K resolution video and the low-latency performance of today’s AR/VR applications are made possible by ongoing advances in HDMI technology. Following the industry shift driven by HDMI 2.2 and its 96 Gbps bandwidth, the HDMI Forum recently announced release 2.2 of the Compliance Test Specification (CTS) for Connectors. To support this update, Allion Labs, a global leader in audio-video device testing and a provider of more than 30 standard certification testing services, now provide complete certification testing and consulting services for HDMI 2.2 Category 4 Connectors.
(Credit: The HDMI Forum)
In accordance with the HDMI Category 4 Connector CTS, the mated pair of connectors must meet the Differential Impedance, Attenuation, and Attenuation-to-Crosstalk Ratio requirements. These test items are identical to those required for Category 3 connectors. In addition, the plug and receptacle mechanical dimensions must also be verified to ensure they fall within the specific tolerances, as the Category 4 connector adopts revised mechanical dimensions to reduce signal attenuation, a change from the long-standing HDMI connector design.
In addition, there are serveral requirements to follow when using HDMI Category 4 connectors into HDMI devices:
- HDMI Category 4 cables must use Category 4 connectors listed on the “Approved Category 4 Connector” list on the HDMI Forum website
- Source/Sink/Repeater devices that support 16Gbps, 20Gbps, 24Gbps bandwidth must use Category 4 connector listed as an “Approved Category 4 Connector” on the HDMI Forum website
- HDMI Category 3 cables must use Category 3 or Category 4 connectors appeared on the Approved Connector List on the HDMI Forum website
- Source/Sink/Repeater devices that support FRL 12Gbps or lower bandwidth must use Category 3 or Category 4 connectors listed the Approved Connector List on the HDMI Forum website
Accelerate Access to the HDMI 2.2 Market
Allion has been an Authorized Testing Center (ATC) since 2021, qualified by the HDMI Forum to perform HDMI 2.X Compliance Testing. We provide end-to-end support, from pre-testing to certification testing.
- Compliance testing: We perform the required test items that include impedance, attenuation, and mechanical dimensions to ensure your product fully comply with the Compliance Test Specification (CTS)
- Experiences team: Our specialists bring extensive experience across Category 1 to Category 4 connector testing, enabling issue identification and improvement guidance.
- Ecosystem advantage: We also support HDMI 2.2-related tests, including signal integrity (SI) and power integrity (PI), covering connectors, cables and end devices. This enables customers to validate the entire ecosystem through one test partner.
- Efficient project support: By streamlining the testing workflow, Allion helps manufacturers shorten development cycles and stay competitive in the fast-moving AV market.
In addition to certification testing, Allion delivers customized test solutions and consulting services to help your products meet the goal of “Time to Market with Quality”. For more information about HDMI certification programs and testing services, please contact us at service@allion.com.