400G Optical Transceiver

400G QSFP-DD DR4

SKU / P/N: PHOS-4Q2FSD45M121

400G DR4 optical transceiver for AI data center, GPU cluster, reseller and system-integrator projects.

Data Rate
425Gbps
Form Factor
single-port QSFP-DD
Standard
DR4
Reach
500m @ SMF
Connector
single MPO-12/APC
Max Power
9W
Spot Available Lead time: 2–4 weeks
Bulk package:
Custom Quote
Custom bulk order? Beyond 2000 pcs, mixed models or annual supply — use Custom Quote to negotiate your discount offline.

Bulk availability changes frequently. Discounts shown are indicative volume tiers — submit an RFQ to confirm the latest price, lead time and allocation. Prices are provided by quote — no public list price.

Link-up guaranteedCoded to any switch / NIC platform
Lifetime warrantyAdvance replacement
Ships from US warehouseFast, no import hassle
Per-unit testedTest report + power-on video

Product description

400GBASE-DR4 QSFP-DD silicon-photonics transceiver — PAM4, 1310 nm, 500 m, DOM (single-mode, MPO-12).

This 400GBASE-DR4 QSFP-DD module is built on an advanced silicon photonics (SiPh) platform. The SiPh chip integrates numerous active and passive optoelectronic components with 3D packaging and a leading-edge 6 nm DSP, making it a cost-effective, lower-power solution for 400GBASE data centers.

The module reaches up to 500 m over single-mode fiber through an MPO-12 connector and complies with the QSFP-DD MSA, IEEE 802.3bs and 400GAUI-8. The 400G Ethernet signal is carried over four parallel lanes, one wavelength per lane, and the module supports 4×100G breakout to QSFP-DR-100G.

Product highlights

  • Silicon-photonics (SiPh) based design for lower power, lower cost and higher density
  • Integrated low-power DSP for stable performance at scale
  • Optimized power budget, max power consumption 9W
  • Compliant with QSFP-DD MSA and IEEE802.3bs standards
  • Supports breakout to lower-rate links for flexible fabric design
  • Backward compatible with existing QSFP form-factor ports

Applications

  • AI data center & GPU cluster interconnect
  • Spine-leaf switching fabric
  • 400G to breakout links in high-density fabrics
  • Hyperscale, cloud and high-performance computing networks

Supply status meaning

In stock or short-notice availability

Data Rate425Gbps
Max Data Rate8x53.125Gbps
Form Factorsingle-port QSFP-DD
StandardDR4
Lanes8
Rate per Lane53.125Gbps PAM4
Reach500m@SMF
MediaSMF
Fiber Typesingle-mode fiber (SMF)
Connectorsingle MPO-12/APC
Connector PolishAPC
Wavelength1311nm
Max Power9W
Operating Temperature0 to 70C (32 to 158F)
Optical Modulation4x100G-PAM4
Electrical Modulation8x50G-PAM4
FECInbuilt FEC: Yes
IEEE ComplianceIEEE802.3bs
MSA ComplianceQSFP-DD MSA
ProtocolsQSFP-DD MSA,IEEE 802.3bs,CMIS5.1
Host Interfacesingle-port QSFP-DD
Warranty5

Four bulk tiers — the larger the volume, the better the discount. Actual pricing is confirmed by RFQ based on quantity, customer tier and lead time; there is no single-unit retail.

PackageQuantityVolume discountBest for
Starter Pack 100 pcs Base bulk price Trial order / small channel Request Quote
Growth Pack 500 pcs Save ~5% vs. Starter Reseller / regular supply Request Quote
Project Pack Popular 1000 pcs Save ~10% vs. Starter AI data center project Request Quote
Strategic Pack 2000 pcs Save ~15% vs. Starter Annual / channel agreement Request Quote
Custom bulk order 2000+ pcs Negotiated offline Annual / strategic supply Contact Sales

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  • Compatible coding for major switch / NIC platforms on request
  • Alternative model recommendations
  • Breakout and cabling guidance

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