clm_531f78966c52441fb7170e0d87087b17_r1

VR2-0313

① SA Source

• Source: 開啟完整 SA 文章
• Section: PCB vs Flyover Cables
• Line hint: 417

Context Before

But now that the NIC is closer to the OSFP cage, the lower speed PCIe Gen6 signal (64Gbit/s per lane uni-directional) travels the longer distance. By making the PCIe Gen6 signal longer, the signal can travel over PCB given that PCIe Gen6 has better signal integrity than the higher speed 200G Ethernet/InfiniBand signal.

PCB vs Flyover Cables

Evidence

Nevertheless, it is still challenging to drive a PCIe Gen6 signal over around 500mm of PCB distance from the Strata Module to the front of the Orchid Module

Context After

First, we must understand why high-speed signals perform worse on PCB versus flyover cables. As SerDes rates increase, high-speed channels become increasingly constrained by insertion loss introduced by PCB traces, vias, dielectric materials and conductor roughness. Insertion loss is defined as the signal power that is lost as a signal is traveling through an interconnect channel.

② Atomic Claim

即使如此，要讓 PCIe Gen6 signal 從 Strata Module 經約 500mm PCB 距離傳到 Orchid Module 前方，仍具有挑戰。

• Epistemic Mode: ASSERTED
• Mapping Status: PARTIAL

③ Semantic Frame

{
  "attribute": "UNSPECIFIED_ATTRIBUTE",
  "context_nodes": [
    {
      "id": "04_knowledge_base/PCB",
      "label": "PCB"
    }
  ],
  "entity": {
    "id": "04_knowledge_base/PCIe",
    "label": "PCIe Gen6"
  },
  "frame_type": "ATTRIBUTE",
  "qualifiers": {
    "condition_text": null,
    "numeric_mentions": [
      "500m"
    ],
    "temporal_mentions": []
  },
  "value": {
    "numeric_mentions": [
      "500m"
    ],
    "value_text": "即使如此，要讓 PCIe Gen6 signal 從 Strata Module 經約 500mm PCB 距離傳到 Orchid Module 前方，仍具有挑戰。"
  }
}

④ Canonical Entity Mapping

Role	Surface Label	Canonical Target
entity	PCIe Gen6	PCIe
context_0	PCB	PCB

⑤ Human Review

請在 Properties 逐項確認：

• 原文 → Atomic Claim 是否忠實
• Atomic Claim → Semantic Frame 是否忠實
• Canonical Entity mapping 是否正確
• Epistemic mode 是否保留原文語氣
• 最後選擇 review_action

Review state

Markdown 內文不是正式 approval。只有 Apply bridge 寫入的 Decision Ledger event 才是正式決策。