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

3.4 TDP1204 DDC Buffer

The TDP1204 has a DDC buffer for HDMI capacitance isolation and for shifting 5-V levels present on the HDMI connector to as low as 1.2-V levels on the GPU source side. The HV_DDC_SDA and HV_DDC_SCL pins support 5-V levels while the LV_DDC_SDA and LV_DDC_SCL pins can support 1.2-V, 1.8-V, and 3.3-V levels.

Note that the TMDS1204 does not provide the DDC buffer function. If level shifting is required, then an external DDC level shifter must be implemented.