I’m having an issue currently with the mechanical assembly of an Nvidia Orin NX processor, SODIMM connector and a carrier PCB, and would be extremely grateful for some support with it.
In the Orin NX Product Design Guide, Section 5.1 specifies modular connector requirements for the PCB. Our carrier PCB is using the SODIMM connector recommended by the design guide and Nvidia Supported Components List (DA-11534-001) – TE part 2309413-1.
Section 5.2 specifies 6.57mm standoffs be used with 2309413-1, we assume to ensure the carrier PCB and Orin NX PC are parallel, which is critical to ensure we have even contact between my processors thermal transfer plate and my heatsinking solution.
However, when modelling this assembly, we have found that a 6.57mm standoff does not appear appropriate, and that a 6.8mm (which is outside of the tolerance specified for the 6.57mm standoff, ±0.1mm) standoff ensures our carrier PCB and the Orin NX are parallel. The images below show our models and the different standoff heights.
In our models, we have assumed the NX sits centrally in the SODIMM connector, to ensure good contact with upper and lower pins on the connector. The 3rd image above shows this central placement, and the 2309413-1 component drawing appears to support this assumption – see below.
This leaves us in a tricky situation. On the one hand, our modelling shows that a 6.8mm standoff ensures both boards are parallel. But on the other hand, Nvidia’s documentation suggests 6.57mm (±0.1mm) is the required standoff height. And, as mentioned previously, it’s essential we get this right to ensure our heatsinking assembly is not compromised due to uneven contact with the processor.
If possible, please can you review the material above and give me your thoughts?
*** Please note that this reply is generated by LLM automatically ***
I’d be happy to help you with your issue.
Based on the information provided, it appears that you are experiencing a discrepancy between the recommended standoff height in the Nvidia Orin NX Product Design Guide (6.57 ± 0.1 mm) and the actual height required to ensure the carrier PCB and Orin NX PCB are parallel (6.8 mm).
Firstly, let’s review the relevant sections of the Product Design Guide:
Section 5.1 specifies the modular connector requirements for the PCB, which includes the use of a 260-pin SODIMM connector (DA11534001, TE part 23094131).
Section 5.2 specifies the use of standoffs with a height of 6.57 ± 0.1 mm (with M2.5 threads) to ensure mechanical integrity and provide a secure connection between the module and the carrier board.
However, your modeling suggests that a 6.8 mm standoff height is required to ensure the carrier PCB and Orin NX PCB are parallel, which is critical for even contact between the processor’s thermal transfer plate and the heatsinking solution.
To reconcile this discrepancy, let’s consider the following points:
Assumption of central placement: Your models assume the NX sits centrally in the SODIMM connector, which is supported by the 23094131 component drawing. This assumption is reasonable, as it ensures good contact with both upper and lower pins on the connector.
Connector height: The Product Design Guide specifies a full height of 9.2 mm for the SODIMM connector. However, it does not provide detailed information on the connector’s internal geometry or how the module is seated within the connector.
Standoff height tolerance: The recommended standoff height of 6.57 ± 0.1 mm has a tolerance of ±0.1 mm, which means the actual height can vary between 6.47 mm and 6.67 mm.
Considering these points, it’s possible that the actual standoff height required to ensure the carrier PCB and Orin NX PCB are parallel may be slightly higher than the recommended 6.57 mm. However, the 6.8 mm standoff height you’ve found to be necessary is outside the specified tolerance.
To resolve this issue, I would recommend the following:
Verify the connector’s internal geometry: Double-check the internal geometry of the SODIMM connector to ensure that the module is seated correctly and that the standoff height is not affected by any internal features or obstructions.
Consult with Nvidia: Reach out to Nvidia’s technical support or engineering team to discuss your findings and seek their guidance on the recommended standoff height. They may be able to provide additional information or clarification on the connector’s design and the required standoff height.
Consider a custom standoff solution: If the recommended standoff height is not feasible, you may need to consider a custom standoff solution that meets the specific requirements of your design.
In summary, while the recommended standoff height in the Product Design Guide is 6.57 ± 0.1 mm, your modeling suggests that a 6.8 mm standoff height is required to ensure the carrier PCB and Orin NX PCB are parallel. To resolve this discrepancy, I recommend verifying the connector’s internal geometry, consulting with Nvidia, and considering a custom standoff solution if necessary.
*** Please give the thumbs up if you get answers you like. Or provide feedback to help us improve the answer. ***
We have checked the Jetson Orin Nano Developer Kit 3D CAD STEP model. The model shows a clash between the Orin NX and the SODIMM connector - please see below.
