In anticipation of market demand for Ultra-High Definition (UHD) displays, which offer four times the resolution of HD video, HDMI Forum published the new HDMI 2.0 specification in September 2013. This was followed by the publication of the corresponding HDMI Compliance Test Specification 2.0 in April 2014. These developments have enabled television manufacturers to begin launching UHD TVs in the 2nd half of 2014.

As the next iteration of HDMI technology, HDMI 2.0 offers significantly more bandwidth (~18 Gbps) to support UHD (2160p@50/60Hz) with 1080p/60 video resolution. HDMI 2.0 also supports up to 32 audio channels with a 1536 kHz audio sample frequency. Besides improving audio/video quality, HDMI 2.0 also enhances overall usability with full backwards-compatibility with earlier HDMI specifications, simultaneous transmission of dual-video streams, and multi-streaming audio to multiple users.

On the more technical side, HDMI 2.0 offers CEC extensions for expanded command and control of consumer electronics devices, support for movie-theater-sized wide-angle 21:9 video aspect ratios, and dynamic synchronization of streaming media. Due to these revolutionary features, HDMI 2.0 can deliver exceptional multimedia entertainment experiences to consumers, both at home and on the go.

Figure 1 : HDMI 2.0 versus HDMI 1.4

The 2014 HDMI Plugfest, hosted by Allion, was attended by the President of HDMI Licensing, LLC., Mr. Steve Venuti and two representatives from Sony’s HDMI Authorized Test Laboratory (Mr. Kei Matsubayashi and Mr. Hiroyuki Funama). Many Taiwan based integrated circuit vendors and instrument manufacturers that are deploying HDMI 2.0 products were also in attendance.

By hosting this event, Allion learned that the majority of HDMI 2.0 products in the development pipeline were sink devices rather than source devices. In general, most HDMI 2.0 source device vendors were from overseas. They also found that only IC components were 6 Gbps compatible and most of these products were in the research and development stage. Next year, some HDMI 2.0 source products should begin to emerge on the market.

The following were some typical product issues that Allion observed during the HDMI 2.0 Plugfest:

Uneven and Equal Line Length

The figure below shows uneven and equal line lengths that were encountered during the 4:2:0 colorimetric testing of a HDMI 2.0 sink device. This product issue will likely impact user satisfaction and result in higher recovery costs and/or customer complaints. After the measurements and extended display identification data was collected for the 2.0 sink devices, that was different than manufactures.

Figure 2

Manufacturers Have Many HDMI 2.0 Design Challenges

HDMI 2.0 Reception IC testing showed a 112 ps intra-pair signal delay, which can cause signal noise and a loss of video. HDMI 2.0 Transmission IC testing also yielded disappointing results with severe problems as observed in the Ultra-Pair Skew and Eye pattern below. These results suggest that manufacturers still have many HDMI 2.0 design challenges ahead.

Figure 3 : 6G Eye Diagram

Bandwidth and Data Transfer performance

The different cables had a significant effect on the test results, especially with bandwidth and data transfer performance. This result emphasizes the importance of complete interoperability testing to make sure the end product does not encounter pairing failure or signal delays due to poor cabling.

“With the various benefits of HDMI 2.0, the greatest technological challenge of all will also be approached in the field of certification testing, particular in 18 Gbps throughput and 4K resolution, so that the reliability and stability of related functions and performance become extremely important,” said Kei Matsubayashi, the representative of SONY HDMI ATC.