SPQ-4E-FR-CDFB Source Photonics Compatible 400GBASE-FR4 QSFP-DD Transceiver
Source Photonics compatible SPQ-4E-FR-CDFB - Key Features
- Compatibility: Source Photonics
- Media Type: Single-Mode Fiber (SMF)
- Connector: Double LC/UPC
- Fiber Count: Duplex
- Maximum Distance: 2 km
- Guaranteed Link Budget: 4 dB
- Tx Wavelength: CWDM 4 Ch
- Supported Data Rate: 425 Gbps
- DDM/DOM: Supported
- Forward Error Correction (FEC): Host FEC Supported
- Temperature Range: Standard 0°-70°C
Source Photonics SPQ-4E-FR-CDFB Price
SKU:400G-QSFP-DD-2.1-MS
Made to Order - 2 WeeksSource Photonics compatible SPQ-4E-FR-CDFB Specifications
Form Factor | QSFP-DD |
Modulation | PAM4 (Pulse Amplitude Modulation 4-level) |
Media Type | Single-Mode Fiber (SMF) |
Connector | Double LC/UPC |
Fiber Count | Duplex |
Maximum Distance | 2 km |
Guaranteed Link Budget | 4 dB |
TX Wavelength | 4-channel CWDM (1271/1291/1311/1331 nm) |
RX Wavelength | 4-channel CWDM (1271/1291/1311/1331 nm) |
Supported Data Rate | 425 Gbps |
Supported Ethernet Applications | 400G Ethernet (425 Gbps) |
DDM/DOM | Supported |
Forward Error Correction (FEC) | Host FEC Supported |
CDR (Clock and Data Recovery) chip | Supported |
Transmitter Type | EML Laser |
Tx Wave Bandwidth | 73 nm (1264.50–1337.50 nm) |
Average Launch Power (Min) Each Lane | -3.3 dBm |
Average Launch Power (Max) Each Lane | 3.5 dBm |
Extinction Ratio (Min) | 3.5 dB |
Receiver Type | PIN photodiode |
RX Wave Bandwidth | 73 nm (1264.50–1337.50 nm) |
Average Receiver Sensitivity (Min) Each Lane | -7.3 dBm |
Average Receiver Sensitivity (Max) Each Lane | 3.5 dBm |
Receiver Overload | 4.5 dBm |
Temperature Range | Standard 0°-70°C |
Storage Temperature | -40° to 85°C |
Relative Humidity | 5 to 85% |
Power Consumption (Max) | 10 W |
Power | +3.3V single power supply |
Compliance | CE, RoHS, Class 1 FDA and IEC60825-1 Laser Safety Compliant, 100G Lambda MSA, 400GBASE-FR4, IEEE 802.3cu, QSFP-DD MSA |
Source Photonics compatible SPQ-4E-FR-CDFB Datasheet
v2Complete technical specifications and product details
Source Photonics compatible SPQ-4E-FR-CDFB Description
SPQ-4E-FR-CDFB is Source Photonics' 400GBASE-FR4 QSFP-DD from their 4E product line. Part number decode: "4E" = 4-electrical-lane host interface, "B" suffix = CDFB revision. Source Photonics also produces a newer variant -- the SPQ-8E2-FR-CDFQA -- with an updated 8-lane electrical interface. EdgeOptic's compatible replacement for the CDFB matches its optical and electrical specifications.
Four CWDM wavelengths (1271/1291/1311/1331 nm), EML transmitters, PIN receivers. PAM4 at 106.25 Gbps per lane for 400G total throughput. LC duplex over OS2 single-mode fiber, 2 km maximum reach. Budget: 4.0 dB (TX -3.3 to +3.5 dBm, RX -7.3 dBm). 11W max power consumption. Detailed optical parameters on the 400GBASE-FR4 product page.
Source Photonics lists a follow-on part, the SPQ-4E-FR-CDFC. Same 400G FR4 standard, same LC duplex connector -- the difference is manufacturing revision level only. When replacing an installed CDFB, verify the exact part number from the transceiver inventory. The variants are functionally identical on the optical side but may carry different internal component revisions.
The SPQ-4E-FR-CDFB is an OEM component that appears in switches from multiple vendors as a factory-installed option. EdgeOptic codes the compatible with vendor-specific EEPROM -- Cisco, Arista, Juniper, Huawei, and others. On Cisco gear, Cisco-recognized EEPROM is used so Nexus and Catalyst accept it without CLI workarounds. Specify the switch vendor when placing the order.
The "4E" means this module uses a 4-electrical-lane host interface -- 4 lanes at 106.25G PAM4 each toward the host ASIC. The module DSP maps these directly to the 4 optical CWDM lanes. Compare that to the SPQ-8E2 series, which splits the same 400G across 8 lanes at 53.125G each. Both deliver identical optical output; the difference is SerDes configuration on the host side. Most modern 400G ASICs support either 4x106.25G or 8x53.125G, so both module generations work in current-generation switch hardware without issues.
IEEE 802.3cu, QSFP-DD MSA HW Rev 5.1, CMIS Rev 4.0 compliant. DOM via two-wire serial interface: optical power per lane, temperature, bias current, supply voltage. Class 1 Laser Product, RoHS. 0 to 70 C commercial operating temperature. KP4 FEC (RS(544,514)) required on the host side.
Volume pricing or multi-vendor coding -- contact our sales team.
Frequently Asked Questions
What is the difference between Source Photonics SPQ-4E-FR-CDFB and SPQ-4E-FR-CDFC?
Both are 400G FR4 QSFP-DD from Source Photonics. CDFC is a later manufacturing revision of the CDFB. Same optical standard, same LC duplex -- internal revision level is the only difference.