400G QSFP-DD Passive DAC Twinax Copper Cable (0.5-3m): 400G-PDAC-QSFP-DD

Our EDGEOPTIC 400G-PDAC-QSFP-DD is a multi-vendor compatible 400G QSFP-DD passive direct attach copper cable designed for ultra-high-performance 400 Gigabit Ethernet and InfiniBand HDR applications within cutting-edge data center environments. The 400G-PDAC-QSFP-DD cable features point-to-point configuration with QSFP-DD (Quad Small Form Factor Pluggable Double Density) connectors on both ends, delivering the highest bandwidth density available for short-reach interconnects between spine and leaf switches, AI/ML training clusters, and hyperscale infrastructure.

The cable supports multi-rate operation from 212.5 to 425 Gbps, accommodating the most demanding bandwidth requirements of modern data center architectures. For Ethernet deployments, the cable handles both 200G Ethernet at 212.5 Gbps and 400G Ethernet at 425 Gbps, supporting the latest generation of hyperscale and cloud infrastructure. The comprehensive InfiniBand support includes EDR at 100 Gbps and HDR at 200 Gbps, making this cable essential for high-performance computing clusters, AI training infrastructure, and GPU-accelerated machine learning environments where maximum interconnect bandwidth directly impacts computational performance.

As a passive DAC solution, the 400G-PDAC-QSFP-DD requires no external power and introduces zero latency to signal transmission, making it the optimal choice for latency-critical applications such as distributed AI training, high-frequency trading systems, and real-time analytics platforms. The cable construction utilizes high-quality twinax copper with optimized wire gauges: AWG30 for lengths from 0.5 to 1.5 meters and AWG28 for lengths from 2 to 3 meters. This wire gauge optimization ensures optimal signal integrity at 50 Gbps PAM4 signaling per lane across eight lanes while maintaining practical cable flexibility for installation in high-density switch environments.

The electrical interface conforms to QSFP-DD MSA specifications, ensuring broad compatibility with standard QSFP-DD host systems from multiple equipment vendors. Our 400G QSFP-DD DAC cables can be encoded for compatibility with major networking vendors supporting next-generation 400G infrastructure. The cable incorporates DDM/DOM (Digital Diagnostic Monitoring) functionality, providing real-time diagnostic data including module temperature and supply voltage through the MSA-compatible interface for proactive network monitoring.

Standards compliance includes IEEE 802.3bj and IEEE 802.3cd for high-speed Ethernet applications alongside InfiniBand EDR and HDR specifications. The cable operates within a 0 to 70°C temperature range, suitable for controlled data center environments. With an MTBF rating of 1,000,000 hours, the cable delivers long-term reliability for mission-critical 400G infrastructure deployments.

Typical deployment scenarios include spine-leaf switch interconnects in hyperscale data centers, GPU cluster connectivity for AI/ML workloads, and high-performance storage fabric backbones. The passive design eliminates power consumption entirely, contributing to greener data center operations.

Our 400G QSFP-DD passive DAC is CE/RoHS certified and compliant with product safety standards. Because our focus is providing top quality service, we perform comprehensive quality checks before delivery including electrical parameter measurements, connector inspection tests, and QSFP-DD EEPROM memory data validation tests.