Description

Farsince 400G QSFP‑DD Active Direct Attach Copper (ACC) cable is a twinax assembly that connects QSFP‑DD 400G ports over copper when reach exceeds passive DAC capability. Each end presents a hot‑pluggable QSFP‑DD interface carrying the 400GAUI‑8 electrical map (8×50G PAM4). Typical uses include ToR to adjacent‑rack switch uplinks, switch‑to‑server NICs and short‑row interconnects in cloud, enterprise and HPC environments where predictable latency and robust signal integrity are required.

An integrated retimed/equalized design extends copper reach while maintaining low latency and link stability. The 28 AWG shielded twinax construction and controlled impedance minimize insertion loss and crosstalk, and an 80 mm minimum bend radius supports clean routing in dense racks. The assembly is interoperable with QSFP‑DD MSA mechanics and CMIS management, and supports IEEE 802.3cd electrical signaling for 50G PAM4 lanes. Farsince offers coding for major switch and NIC platforms, custom lengths and labeling, and provides lot‑level test reports for consistent deployment.

Specifications

• Product Type: 400G Active Direct Attach Copper (ACC) Twinax
• Host Interface: QSFP‑DD to QSFP‑DD
• Data Rate: 400 Gbps aggregate (400GAUI‑8)
• Modulation: 8×50G PAM4, retimed/equalized
• Wire Gauge: 28 AWG
• Minimum Bend Radius: 80 mm
• Cable Structure: Shielded twinax, active electronics at both ends
• Power Design: ≤2.5 W per end
• Installation: Hot‑pluggable with pull‑tab latches
• Operating Temperature: 0 to +70°C
• Jacket Material: PVC
• Application: Short‑range 400G switch‑to‑switch/NIC links inside data halls
• Compatibility: QSFP‑DD MSA, CMIS; IEEE 802.3cd electrical interface
• Compliance: RoHS, REACH
• Customization: Vendor coding, length and labeling available