SLLA598 October   2022 TDP1204 , TMDS1204

 

  1.   Abstract
  2.   Trademarks
  3. 1Introduction
  4. 2HDMI2.1 Key Features
    1. 2.1 Bandwidth
    2. 2.2 Dynamic HDR
    3. 2.3 Auto Low-Latency Mode
    4. 2.4 Variable Refresh Rate
    5. 2.5 Quick Frame Transport
    6. 2.6 Quick Media Switching
    7. 2.7 Enhanced Audio Return Channel
  5. 3TDP1204 and TMDS1204
    1. 3.1 TMDS1204 Fan-Out Buffer
    2. 3.2 TMDS 1204 SIGDET_OUT
    3. 3.3 TMDS1204 DC Gain Adjustment
    4. 3.4 TDP1204 DDC Buffer
  6. 4Summary
  7. 5References

2.1 Bandwidth

Most HDMI displays currently support the HDMI 2.0 standard, which has a bandwidth up to 18 Gbps. The 18 Gbps bandwidth can support an uncompressed 4k signal at 60 frames per second at up to eight-bit color. HDMI 2.1, with its 48 Gbps bandwith, adds support for an uncompressed 8k signal at 60 frames per second in 12-bit color. Using display stream compression (DSC), HDMI 2.1 can even push to 10K signal at 120 frames per second in 12- bit color.

Along with the increased bandwidth, it also introduces a new electrical mode of operation called Fixed Rate Link (FRL). With FRL, the existing TMDS data lane 0 to 2 are re-defined as FRL data lane 0 to 2. The TMDS clock lane are re-defined as FRL data lane 3. HDMI2.1 supports the following FRL rate and lane control.

  • 3 Gbps on 3 lanes
  • 6 Gbps on 3 lanes
  • 6 Gbps on 4 lanes
  • 8 Gbps on 4 lanes
  • 10 Gbps on 4 lanes
  • 12 Gbps on 4 lanes

Note when in the FRL 3 lanes operating mode, the FRL data lane 3 is not being used.