DS160PR810: PCIe 4.0 board budget and re-driver vs re-timer selection

Eddie Chou

Expert 5610 points

Part Number: DS160PR810
Other Parts Discussed in Thread: DS160PR421, DS160PR412, TS3DV642

Hi Team,

Below is PCIe 4.0 application block diagram,

From slot 9 (re-driver) to Main board (CPU) total trace is 14.5" (BB connector not include)

If customer use Mid-Loss PCB with -2.28dB/inch, the total PCB loss will be -33.089 dB loss.

Customer would like confirm with us if DS160PR810 can compensate the insertion loss or they need DS160PT810 re-timer for this case?

Thanks & Regards

Eddie Chou.

over 2 years ago

0 Nasser Mohammadi over 2 years ago

TI__Guru* 93670 points

Hi Eddie,

In a PCIe Gen4 environment - without a redriver - root complex and end point are expected to be able to compensate for 28dB total channel loss. Based on our evaluation, with a redriver we can extend this reach to 44dB total channel loss. However, it is recommended to keep pre-channel loss to 30dB or lower. Given this, it is recommended to reduce the loss to 30dB instead.

Additionally please note upstream signals - from GPU to the CPU direction - are going to see a similar loss as well. Therefor we should have redriver both on the slot_9 and MB close to the CPU.

Regards,Nasser

0 Eddie Chou over 2 years ago in reply to Nasser Mohammadi

TI__Expert 5610 points

Hi Nasser,

Happy Holidays,

Below are schematic and block diagram update from customer, please help us check comments once you back to work, thanks.

cPCI-A3MXM_20221223_1.pdf

Thanks & Regards

Eddie

0 Nasser Mohammadi over 1 year ago in reply to Eddie Chou

TI__Guru* 93670 points

Hi Eddit,

How about instead of using DS160PR810 and TS3DV we use DS160PR412 on TX side and DS160PR421 on the RX side? Please review this with your customer and let me know their feedback.

Regards,Nasser

0 Eddie Chou over 1 year ago in reply to Nasser Mohammadi

TI__Expert 5610 points

Hi Nasser,

TS3DV642 is multiplexer for DP and HDMI not for PCIe 4. PCIe 4 only need re-Driver.

Thanks & Regards

Eddie Chou

0 Nasser Mohammadi over 1 year ago in reply to Eddie Chou

TI__Guru* 93670 points

Hi Eddie,

DS160PR412/421 are multiplexers as well. You can disable RX detect and use these parts for non-PCIe applications as well. Do you have access to the data sheet for these parts? You can review these and let customer take a look as well.

Regards,Nasser

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

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DS160PR810: PCIe 4.0 board budget and re-driver vs re-timer selection