Description

Farsince 800G OSFP‑to‑2×QSFP112 passive breakout DAC is a copper twinax assembly that fans out one OSFP 800G finned‑top port into two independent 400G QSFP112 interfaces. The OSFP end carries eight 100G PAM4 electrical lanes (800GAUI‑8), mapped as 2× four‑lane 400G (400GAUI‑4) on the QSFP112 legs. This assembly is commonly used to connect an 800G switch to two 400G server or accelerator NICs in dense racks, enabling flexible port utilization in AI clusters, spine‑leaf networks and scale‑out storage where reach is short and latency must be minimal.

The passive design adds virtually no latency and requires only identification/management power, while the finned‑top OSFP housing supports cages with integrated heat sinks for improved thermal margin. Controlled‑impedance 28 AWG pairs and full shielding help maintain low insertion loss and crosstalk; a 40.5 mm minimum bend radius eases routing in crowded cable trays. The cable is hot‑pluggable and interoperable with OSFP and QSFP112 MSA mechanics, CMIS 5.0 management and IEEE 802.3ck electrical specifications. Farsince provides platform coding, custom lengths, labeling and lot‑level test reports to simplify volume deployment.

Specifications

• Product Type: Passive Direct Attach Copper Breakout Twinax
• Host Interface: OSFP 800G, finned‑top
• Device Interface: 2× QSFP112 400G
• Data Rate: 800 Gbps aggregate; 2× 400 Gbps legs
• Modulation: OSFP 8×100G PAM4 to each QSFP112 4×100G PAM4
• Wire Gauge: 28 AWG
• Cable Structure: Shielded twinax, Y‑breakout, passive copper
• Minimum Bend Radius: 40.5 mm
• Power Design: Passive; ≤0.1 W per end for ID/CMIS
• Installation: Hot‑pluggable pull‑tab latches (OSFP and QSFP112)
• Operating Temperature: 0 to +70°C
• Jacket Material: PVC
• Application: Breakout from 800G switch to dual 400G NICs in data centers
• Compatibility: OSFP MSA, QSFP112 MSA, CMIS Rev 5.0, IEEE 802.3ck
• Compliance: RoHS, REACH
• Customization: Vendor coding, length and labeling available