SN75DP126: schematic check

GARETH OU

Mastermind 9415 points

Part Number: SN75DP126

1.Could you help check the SN75DP126 schematic as below and any need to adjust?

Thank you

over 3 years ago

0 David (ASIC) Liu over 3 years ago

TI__Guru**** 150790 points

Hi,

1. Please make sure the DP output is AC-coupled.

2. Please make sure the AUX has the right pullup/pulldown

3. Please make sure the DDC is pulled up, 2k for source application, 47k for sink application

4. HDMI HPD is 5V while DP HPD is 3.3V

5. Please make sure there is pullup on SCL_CTL and SDA_CTL

6. Do you want to connect the CAD_SRC to the source?

Thanks

David

0 GARETH OU over 3 years ago in reply to David (ASIC) Liu

Mastermind 9415 points

Hi David

1. Please help to confirm whether SN75DP126 has a separate file layout guide? Because the DS is relatively rough.
Need to have Trace length (max/min), Length mismatch, spacing and other information.

2. Another problem is that the Impedance of Input DDI3 & TBT3 in the INTEL guide is 85 ohm, but the Impedance of SN75DP126 is 100 ohm.
So for Impedance, I set 85 ohm for DDI3 input, 85 ohm for DP output, and 100 ohm for HDMI output. Will this be a problem?

Thank you

0 David (ASIC) Liu over 3 years ago in reply to GARETH OU

TI__Guru**** 150790 points

Hi,

1. Would you please accept my friendship request so I can send you the DP126 EVM layout guide as a reference?

2. I would keep the input impedance to be 85ohm to satisfy the Intel requirement, but keep the DP and HDMI output to be 100ohm to satisfy the DP and the HDMI requirement.

Thanks

David

0 GARETH OU over 3 years ago in reply to David (ASIC) Liu

Mastermind 9415 points

Hi David

could you please reconfirm

DDI: 85 ohm / HDMI 100 ohm / DP 85 ohm or 100 ohm ?

Thanks you

0 David (ASIC) Liu over 3 years ago in reply to GARETH OU

TI__Guru**** 150790 points

Hi,

I would follow the 85ohm impedance requirement. The board file has been sent to you, please check.

Thanks

David

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SN75DP126: schematic check