SPTSHP3CLCDF Silicom Compatible 400GBASE-FR4 QSFP-DD Transceiver

EdgeOptic's SPTSHP3CLCDF compatible is a Silicom-coded 400GBASE-FR4 QSFP-DD transceiver, with the same 2 km duplex single-mode reach, the same LC duplex connector, and the same optical and electrical envelope as the original SPTSHP3CLCDF. The module follows the SPTSHP3 part-number lineage, appearing alongside Silicom's SmartNIC and network adapter product line.

Don't confuse the two SPTSHP3 SKUs. SPTSHP3CLCDF is 400GBASE-FR4 with an LC duplex connector, 2 km reach, single-mode duplex fiber. SPTSHP3PMCDF is 400GBASE-DR4 with an MPO-12 connector, 500 m reach, single-mode parallel fiber. Different connector, different fiber plant, different reach class. Verify the suffix on the chassis transceiver table or the installed-module label before ordering, since the FR4 and DR4 builds are not interchangeable in the field.

Four CWDM wavelengths at 1271, 1291, 1311, and 1331 nm multiplex onto a single duplex LC pair. PAM4 modulation at 53.125 GBaud per lane delivers 400 Gb/s aggregate throughput. EML transmitters drive each wavelength channel; PIN photodiode receivers handle the inbound side. TX power is -3.3 to +3.5 dBm per lane, RX sensitivity is -7.3 dBm. The 4 dB optical link budget covers a 2 km OS2 span with margin for patch panels and splices in normal data center cabling. Maximum power consumption 10 W. Full 400GBASE-FR4 specifications cover the rest.

The SPTSHP3CLCDF lands in two deployment patterns. The first is server-side QSFP-DD on SmartNIC and network adapter ports, where Silicom's primary product line drives 400G fabric uplinks from a compute node directly to a top-of-rack switch over single-mode fiber. The second is switch QSFP-DD on standard data center leaf and spine platforms. EdgeOptic codes the EEPROM for the target host at build time, whether that is a NIC vendor or a switch chassis vendor. Specify the NIC or switch platform on the order so the module ships pre-coded for the host hardware.

Conforms to IEEE 802.3cu-2021, 100G Lambda MSA 400G-FR4, QSFP-DD MSA, and CMIS 4.0. CMIS exposes per-lane TX and RX optical power, module case temperature, supply voltage, and laser bias current over standard I2C, so DOM integrates with existing chassis or NIC monitoring through the host diagnostic stack. KP4 RS-FEC, RS(544,514), is required from the host ASIC at 400G to meet the PAM4 BER target. Class 1 laser safe per IEC 60825-1, CE and RoHS certified, 0 to 70 °C commercial operating temperature.

FR4 fits 400G data center interconnect, leaf-spine uplinks, and increasingly server-side fabric links into GPU and HPC compute nodes where each node draws high-bandwidth traffic from the network fabric. Duplex LC patching keeps structured cabling simple where the existing single-mode plant already runs LC, the alternative to MPO-12 parallel optics on DR4. A 2 km reach covers most intra-campus and metro-edge runs.

Backed by 15+ years of EdgeOptic compatibility engineering across vendor optical platforms. Made to order with a 2-week lead time and lifetime warranty included. For volume pricing or platform-specific EEPROM coding requests, contact our sales team.