40G CWDM4 QSFP+ ELR4 Transceiver for 20km SMF Links, Duplex LC
QSFP+40-CW4-20(ELR4)-LCD
- Broad Multi-Brand Compatibility
- Flexible Customization Support
- Tested for Reliable Performance
- Fast Response & Delivery
- Professional Technical Support
The FC-LINK QSFP+ 40G CWDM4 20km ELR4 LC DX transceiver is a high-performance solution for 40GBASE Ethernet, supporting data transmission over single mode fiber (SMF) at distances of up to 20km. Operating at a wavelength of 1310nm and utilizing duplex LC connectors, it complies with SFF-8436 QSFP+ MSA and RoHS standards. Equipped with digital diagnostics accessible via the I2C interface, this hot-swappable transceiver provides real-time monitoring of operating parameters, making it an ideal choice for data centers, high-performance computing, and enterprise core and distribution networks.
| SPECIFICATIONS | |||
|---|---|---|---|
| Product Model | QSFP+40-CW4-20(ELR4)-LCD | Manufacturer Brand | FC-LINK |
| Package Type | QSFP+ | Optical Connector | LC Duplex |
| Max Data Rate | 40Gbps | Channel Data Rate | 10.3125Gbps |
| Effective Transmission Distance | 20km | ||
| Wavelength | 1271nm 1291nm 1311nm 1331nm | Operating Voltage | 3.3V |
| Fiber Type | SMF | Core Size | 9/125µm |
| Transmitter Type | DFB CWDM | Receiver Type | PIN |
| TX Power | -4.5~2.3dBm | Receiver Sensitivity | <-12.5dBm |
| Digital Diagnostic Monitoring(DDM) | YES | Receiver Overload | 3.3dBm |
| Power Consumption | ≤3.5W (Commercial) ≤4.5W (Industrial) | Protocols | SFF-8436 QSFP MSA |
| Operating Temperature(Commercial) | 0℃~+70℃ | Storage Temperature(Commercial) | -40℃~+85℃ |
| Operating Temperature(Industrial) | -40℃~+85℃ | Storage Temperature(Industrial) | -40℃~+85℃ |
Server-to-Switch Data Center Links
Used for 10G/25G/100G optical uplinks between servers and top-of-rack switches in high-density data center deployments.
Building-to-Building Campus Backbone
Suitable for 1G/10G fiber links between office buildings, campus distribution rooms, and backbone aggregation points.
Access-to-Core Enterprise Uplinks
Designed for switch uplinks from access to aggregation or core layers in enterprise and campus network architectures.
Industrial Switching in Harsh Environments
Applied in industrial Ethernet, automation systems, and outdoor cabinets where wider temperature tolerance and stable fiber communication are required.
Compatible Brands
Customization Options
Vendor Coding
Private Label
Custom Part Number
Packaging Design
Temperature Grade Selection
| Absolute Maximum Ratings | |||||||||
| Parameter | Symbol | Min. | Max. | Unit | |||||
| Storage temperature | TS | -40 | +85 | °C | |||||
| Supply voltage | VCC | -0.5 | 3.6 | V | |||||
| Operating relative humidity | RH | 0 | 85 | % | |||||
| *Exceeding any one of these values may destroy the device immediately. | |||||||||
| Recommended Operating Conditions | |||||||||
| Parameter | Symbol | Min. | Typical | Max. | Unit | ||||
| Operating case temperature | Tc | 0 | - | +70 | °C | ||||
| Power supply voltage | Vcc | 3.15 | 3.3 | 3.45 | V | ||||
| Power supply current | Icc | - | - | 1100 | mA | ||||
| Power dissipation | PD | - | - | 3.5 | W | ||||
| Aggregate bit rate | BRAVE | - | 41.25(40GE) | - | Gbps | ||||
| Lane bit rate | BRLANE | - | 10.3125(40GE) | - | Gbps | ||||
| Performance Specifications-Electrical | |||||||||
| Parameter | Symbol | Min. | Typ. | Max | Unit | Notes | |||
| Transmitter | |||||||||
| Single ended input voltage tolerance | - | -0.3 | - | 4 | V | Referred to TP1 signal common | |||
| Differential input amplitude | - | 150 | - | 1000 | mvp-p | - | |||
| AC common mode input voltage tolerance | - | 15 | - | - | mV | RMS | |||
| Input impedance(differential) | Zin | 85 | 100 | 115 | ohms | Rin > 100 kohms @ DC | |||
| TX Disable | Disable | VIH | 2 | - | Vcc+0.3 | V | - | ||
| Enable | VIL | 0 | - | 0.8 | - | ||||
| TX FAULT | Fault | VOH | 2.4 | - | Vcc+0.3 | V | - | ||
| Normal | VOL | 0 | - | 0.8 | - | ||||
| Receiver | |||||||||
| Single ended output voltage | - | -0.3 | - | 4 | V | Referred to ignal common | |||
| Differential output amplitude | - | 290 | - | 1000 | mvp-p | - | |||
| AC common mode voltage | - | - | - | 7.5 | mV | RMS | |||
| Termination mismatch at 1MHz | - | - | - | 5 | % | - | |||
| Output impedance(differential) | Zout | 85 | 100 | 115 | ohms | - | |||
| Output rise/fall time | tr/tf | 30 | - | - | ps | 10%~90% | |||
| RX_LOS | LOS | VOH | 2.4 | - | Vcc+0.3 | V | - | ||
| Normal | VOL | 0 | - | 0.8 | V | - | |||
| Optical and Electrical Characteristics | |||||||||
| Parameter | Symbol | Min. | Typical | Max. | Unit | ||||
| SMF | L | - | 10 | - | km | ||||
| Aggregate bit rate | BRAVE | - | 41.25 | - | Gbps | ||||
| Per lane bit rate | BRLANE | - | 10.3125 | - | Gbps | ||||
| Transmitter | |||||||||
| Channels wavelength | λC | 1264.5 | 1271 | 1277.5 | nm | ||||
| 1284.5 | 1291 | 1297.5 | |||||||
| 1304.5 | 1311 | 1317.5 | |||||||
| 1324.5 | 1331 | 1337.5 | |||||||
| -20dB spectral width | ∆λ | - | - | 1 | nm | ||||
| Average launch power, each lane | Pout/lane | -3.5 | - | 2.3 | dBm | ||||
| Extinction ratio | Er | 3.5 | - | - | dB | ||||
| Output optical eye | IEEE 802.3ba-2010 Compliant | ||||||||
| Receiver | |||||||||
| Channels wavelength | λC | 1264.5 | 1271 | 1277.5 | nm | ||||
| 1284.5 | 1291 | 1297.5 | |||||||
| 1304.5 | 1311 | 1317.5 | |||||||
| 1324.5 | 1331 | 1337.5 | |||||||
| Damage threshold | 5.5 | - | - | dBm | |||||
| Receiver sensitivity in OMA, each lane | Pmins | - | - | -12.5 | dBm | ||||
| Maximum receive power, each lane | Pmax | 2.3 | - | - | dBm | ||||
| Receiver reflectance | Rr | - | - | -26 | dB | ||||
| Los de-assert | LOSD | - | - | -15 | dBm | ||||
| Los assert | LOSA | -24 | - | - | dBm | ||||
| Los hysteresis | - | 0.5 | - | - | dB | ||||
| Functional Description of Transceiver |
| QSFP+ Transceiver Electrical Pad Layout |
| Pin Arrangement and Definition | |||||||||
| Pin | Logic | Symbol | Description | Plug Sequence | Notes | ||||
| 1 | - | GND | Ground | 1 | 1 | ||||
| 2 | CML-I | Tx2n | Transmitter Inverted Data Input | 3 | - | ||||
| 3 | CML-I | Tx2p | Transmitter Non-Inverted Data Input | 3 | - | ||||
| 4 | - | GND | Ground | 1 | 1 | ||||
| 5 | CML-I | Tx4n | Transmitter Inverted Data Input | 3 | - | ||||
| 6 | CML-I | Tx4p | Transmitter Non-Inverted Data Input | 3 | - | ||||
| 7 | - | GND | Ground | 1 | 1 | ||||
| 8 | LVTTL-I | ModSelL | Module Select | 3 | - | ||||
| 9 | LVTTL-I | ResetL | Module Reset | 3 | - | ||||
| 10 | - | VccRx | +3.3V Power Supply Receiver | 2 | 2 | ||||
| 11 | LVCMOS- I/O | SCL | 2-wire Serial Interface Clock | 3 | - | ||||
| 12 | LVCMOS- I/O | SDA | 2-wire Serial Interface Data | 3 | - | ||||
| 13 | - | GND | Ground | 1 | 1 | ||||
| 14 | CML-O | Rx3p | Receiver Non-Inverted Data Output | 3 | - | ||||
| 15 | CML-O | Rx3n | Receiver Inverted Data Output | 3 | - | ||||
| 16 | - | GND | Ground | 1 | 1 | ||||
| 17 | CML-O | Rx1p | Receiver Non-Inverted Data Output | 3 | - | ||||
| 18 | CML-O | Rx1n | Receiver Inverted Data Output | 3 | - | ||||
| 19 | - | GND | Ground | 1 | 1 | ||||
| 20 | - | GND | Ground | 1 | 1 | ||||
| 21 | CML-O | Rx2n | Receiver Inverted Data Output | 3 | - | ||||
| 22 | CML-O | Rx2p | Receiver Non-Inverted Data Output | 3 | - | ||||
| 23 | - | GND | Ground | 1 | 1 | ||||
| 24 | CML-O | Rx4n | Receiver Inverted Data Output | 3 | - | ||||
| 25 | CML-O | Rx4p | Receiver Non-Inverted Data Output | 3 | - | ||||
| 26 | - | GND | Ground | 1 | 1 | ||||
| 27 | LVTTL-O | ModPrsL | Module Present | 3 | - | ||||
| 28 | LVTTL-O | IntL | Interrupt | 3 | - | ||||
| 29 | - | VccTx | +3.3V Power supply transmitter | 2 | 2 | ||||
| 30 | - | Vcc1 | +3.3V Power supply | 2 | 2 | ||||
| 31 | LVTTL-I | LPMode | Low Power Mode | 3 | - | ||||
| 32 | - | GND | Ground | 1 | 1 | ||||
| 33 | CML-I | Tx3p | Transmitter Non-Inverted Data Input | 3 | - | ||||
| 34 | CML-I | Tx3n | Transmitter Inverted Data Input | 3 | - | ||||
| 35 | - | GND | Ground | 1 | 1 | ||||
| 36 | CML-I | Tx1p | Transmitter Non-Inverted Data Input | 3 | - | ||||
| 37 | CML-I | Tx1n | Transmitter Inverted Data Input | 3 | - | ||||
| 38 | - | GND | Ground | 1 | 1 | ||||
| 1: GND is the symbol for signal and supply (power) common for the QSFP+ module. All are common within the QSFP+ module and all module voltages are referenced to this potential unless otherwise noted. Connect these directly to the host board signal-common ground plane. | |||||||||
| 2: Vcc Rx, Vcc1 and Vcc Tx are the receiver and transmitter power supplies and shall be applied concurrently. Requirements defined for the host side of the Host Edge Card Connector are listed in Table 6. Recommended host board power supply filtering is shown in Figures 3 and 4. Vcc Rx Vcc1 and Vcc Tx may be internally connected within the QSFP+ Module in any combination. The connector pins are each rated for a maximum current of 500mA. | |||||||||
Performance Testing
Each module is tested before shipment to help ensure stable optical and electrical performance.
Compatibility Verification
Compatibility validation is available for major switch and router platforms.
Reliability Screening
Selected products support aging, temperature cycle, and stability testing for demanding applications.
Traceable Quality Control
Inspection and production records support more consistent quality control and batch traceability.
