Intel WGi210IT packet loss at temperatures >= 65C

[Jean-Francois]

Hello intel,

I am facing an issue with packet losses on the i210IT (WGI210IT S LJXS, procured from Mouser) on several PCBa, only when operating at a link speed of 1Gbps. I have tested operation @ 100Mbps using an external 100Mbps switch and I do not face this issue.

Here is our current configuration:

- External crystal (ECS-250-18-33-JGN-TR), ±30PPM frequency stability, ±20PPM frequency tolerance, with 27pF load capacitance and rated -40/+85C, ESR of max 40R, drive level of 100uW. The load capacitors are C0G/NP0

- Using the i210 internal power rails for +1.5Vcc and +0.9Vcc. Considering the DC bias of the capacitors used, we have ~41.2uF effective on +1.5Vcc and ~ 47.1uF effective on +0.9Vcc

- Using a dedicated magnetic (S558-5999-P3-F) rated for -40/+85C and validated already on other designs. Based on the intel reference design guide, the center-tap on the i210 side are tied together, with 0.1uF per center-tap and 1uF global.

- 100R differential impedance on the PCB layout without any disruptions / traces routed over a plane split. The MDI pairs have a solid GND reference (on L2) and the impedance control has been verified with the PCB manufacturer.

- The stackup is 4-Layer, 1oz external copper thickness, 1oz internal copper thickness

The issue:

Either in a PING configuration with a switch outside the thermal chamber or by doing MAC-to-MAC transaction, we observe a gradually increasing quantity of packet being lost when exceeding 65C, with packet losses ~ 70% at 85C.

Here are the steps taken, to date, to try and diagnose the issue:

1) Our design has no heatsinking solution due to our operating environment (industrial, must have 0 moving parts). Thus we designed and implemented a custom heatsink, and we measured the IC temperature using a thermocouple following Intel recommendation in the i210 datasheet: at 85C ambient temperature, the IC stabilizes to 97C, which is below the maximum junction-case temperature of 105C. I was expecting this to solve our issue, but it did not, we still see an unusual high amount of packets being lost at >= 65C.

2) We have used the lanconf tool to re-perform IEEE compliance test at ambient temperature, and all tests passed successfully at all speeds (10Mbps, 100Mbps, 1Gbps).

3) We have used the lanconf tool with our ethernet card installed in thermal chamber to setup the i210 in internal MAC loopback, internal PHY loopback, and external loopback. These 3 tests were executed successfully at 85C for 100M+ packets, there were no "Data verify failures"

4) I have tried to change the crystal to a precision oscillator (±1.5PPM) without luck, still seeing the same packet loss issue @ 1Gbps at >= 65C

5) I have tried reworking our PCBa to power the i210IT using external regulator instead of the internal ones, without luck, still seeing the same packet loss issue @ 1Gbps at >= 65C

I am out of ideas, can you please help us investigate this issue? I have a hard time figuring out where the bug might be and felt like I have tried every possible ways.

Thank you!

[Sazirah]

Hi Jean-Francois,

Thank you for contacting Intel Community Forum.

Upon checking, we have our dedicated team Intel Embedded team that is expertise in this product issue that you reported. We will transfer this forum to Embedded team, kindly give them some time to get back to you.

Regards,

Sazzy_Intel

[CarlosAM_INTEL]

Hello,  @Sazirah :

Thank you for contacting Intel Embedded Community.

We need to clarify that this forum is not related to an Intel Embedded Platform.

Due to this, the customer request is out of our scope of support.

Please consider this information when you provide the previous suggestion, or transfer any forums to the channel that you mentioned in your previous communication.

Best regards,

@CarlosAM_INTEL.