TS3DV642: AC cap for DP/HDMI application

Roy Hsu

Genius 9390 points

Part Number: TS3DV642

Hi Team,

Why are ac caps needed for DP applications but not HDMI applications?

Is DP common mode voltage higher than 3.6V?

Thanks!

Roy

over 2 years ago

0 David (ASIC) Liu over 2 years ago

TI__Guru**** 177776 points

Roy

The DP spec requires its interface to be AC coupled while HDMI1.4 and 2.0 require the source to be DC-coupled, and sink supports both AC and DC-coupling. HDMI2.1 now support source to be AC-coupled.

The common mode voltage for DP is 0 to 2V.

Thanks

David

0 Roy Hsu over 2 years ago in reply to David (ASIC) Liu

TI__Genius 9390 points

Hi David,

I'm confused. If the common mode voltage for DP is 0 to 2V, why would the DP spec mandates its interface to be ac coupled? Is it related to insertion loss/signal integrity?

Thanks!

Roy

0 David (ASIC) Liu over 2 years ago in reply to Roy Hsu

TI__Guru**** 177776 points

Roy

1. AC coupling would help remove common mode voltage if a device's common mode voltage is out of spec

2. Provide EOS protection

Thanks

David

Interface

Interface forum

TS3DV642: AC cap for DP/HDMI application