TLK10232: Notes on using 1G

Hi Nishie-san,

Could you add some additional details to this?  How is the TLK10232 being configured?  Is this being used in a front port or backplane application?  Is the 10G link 10G-KR with auto negotiation and link training, or are these disabled?

Without knowing many system details, I would speculate if the TLK10232 might need a 1G specific configuration in order to get 1G link up.  If you are able to get 10G link up, I would be surprised if signal integrity is causing link down at 1G.

Thanks,

Drew

Hi Drew-san,

Thank you for your support.

"How is the TLK10232 being configured? "

->Customers are using TLK 10232 as a bridge between the SFP module and Ethernet.

   If the customer accepts, expand the schematic.

"Is this being used in a front port or backplane application?"

->Probably the front port.

"Is the 10G link 10G-KR with auto negotiation and link training, or are these disabled?"

->I will check with the customer.

Best Regards,

Nishie

Hi Nishie-san,

Thanks for following up on this.  Please also share any MDIO configuration the customer is doing to the TLK10232.

Regarding sharing the schematic or other confidential material, feel free to send me a direct message on E2E since this is a public thread.

Thanks,

Drew

Hi Drew-san,

I sent you a private message.

Best Regards,

Nishie

Nishie:

   Response maybe delayed due to holiday.

Hi Brian-san

Thank you for your reply.

I understand that response delayed due to holiday.

It's no problem if you respond after returning from holiday.

Best Regards,

Nishie

Hi Nishie-san,

Apologies for the delay, I was out of office over the holidays.  I suspect the issue is that 10G data is 64b/66b encoded, while 1G data is 8b/10b encoded.  The TLK10232 needs to be configured accordingly.  Is auto-negotiation enabled?  If so, I would expect it to handle this transition between 10G and 1G.  If not, try using the registers below to select 1G mode.

Thanks,

Drew

Hi Drew-san,

Thank you for your reply.

The TLK10232 needs to be configured accordingly.

->Does "configured accordingly" mean that the TLK10232 set 10G-KR/1G-KX (Determined by Auto Neg) listed in Table2-3.TLK 10232 Operating Mode Selection?

Best Regards,

Nishie

Hi Nishie-san,

Apologies for not being more clear.  In this case, I meant that the TLK10232 needs to be configured to match the data encoding of the high speed data.  For 10G, this is 64b/66b encoding, and for 1G this is  8b/10b encoding.

If auto-negotiation is enabled, the TLK10232 should automatically handle this.  However, based on the block diagram you sent, it appears that this is being used in a front port application.  Typically auto-negotiation is not enabled in a front port application.  Assuming auto-negotiation is disabled, please follow the description for SW_PCS_SEL to select between 1G and 10G mode. Please let me know if this helps resolve the issue.

Thanks,

Drew

Hi Drew-san,

Thank you for your detailed explanation.

I would like to confirm with our customer based on what you have provided.

I would like to get feedback from our customer and discuss it again if any questions arise.

Best Regards,

Nishie