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Finisar FWLF1634RL25 DWDM 4.25G FC SFP 1557.36nm 80km
up to 4.25 Gb/s DWDM 4.25G FC / 2.5G, APD rx (non-rate-select) SFP transceiver, 1557.36nm (192.5THz, ITU ch25), up to 80km, commercial (−5 to 70 °c) temperature.
- Manufacturer
- Coherent Corp. (formerly Finisar / II-VI)
- Mfr part number
- FWLF1634RL25
- Family
- FWLF1634RL
- Category
- Fiber optic transceiver modules
- Datasheet
- FWLF1634RL25 datasheet (PDF)
FWLF1634RL25 specifications
| Attribute | Value |
|---|---|
| Manufacturer | Coherent Corp. (Finisar) |
| Manufacturer part number | FWLF1634RL25 |
| Product family | FWLF1634RL |
| Form factor | SFP |
| Standards / application | 4x FC; 1x/2x FC, GbE and OC-48 LR-2 (rate-select option) |
| Data rate | 0.155–4.25 Gb/s |
| Wavelength | 100 GHz ITU grid C-band, 45 channels: ch17 191.7 THz/1563.86 nm to ch61 196.1 THz/1528.77 nm |
| Laser | Temperature-stabilized DWDM-rated low-dispersion DFB |
| Receiver | APD |
| Reach | Total link budget 26–30 dB @4.25 Gb/s; 31–34 dB @2.5 Gb/s (BER<10⁻¹²) |
| Tx output power | +2 to +5 dBm |
| Rx sensitivity | −28 dBm @2.5 Gb/s; −23 dBm @4.25 Gb/s (BER<10⁻¹²) |
| Rx overload / max input | −9 dBm; damage threshold +6 dBm |
| Extinction ratio | 6.0 dB (≤4.25G); 8.2 dB SONET (rate-select option) |
| Supply voltage | 3.3 V (3.13–3.50 V) |
| Power dissipation | 1.25 W max (Icc 325 mA typ) |
| Operating temperature | Commercial (−5 to 70 °C) |
| Diagnostics | Digital diagnostics per Finisar AN-2030; enhanced features per DWDM SFP MSA (A2h: laser current, temperature, Tx/Rx power) |
| Compliance | Class 1 laser product |
| Lifecycle | Current production |
| Variant note | y = L: non rate select; ITU 100 GHz channel 25 (ordering table: 25 = 192.5 THz) |
Optical and electrical values are from the Finisar / Coherent family datasheet; temperature grade is per part number. Confirm critical values with us before ordering.
About the Finisar FWLF1634RL25
The Finisar FWLF1634RL25 (now a Coherent Corp. product, formerly II-VI) is a SFP DWDM 4.25G FC / 2.5G, APD rx (non-rate-select) optical transceiver for up to 4.25 Gb/s links at 1557.36nm (192.5THz, ITU ch25) over SMF, with reach up to 80km. It is a commercial-temperature part rated −5 to 70 °C. It belongs to Finisar's FWLF1634RL family, which has 45 orderable variants that differ by temperature grade, latch, receiver build or wavelength channel. Typical uses: Gigabit Ethernet, 1/2/4G Fibre Channel SAN, SONET OC-48 / STM-16 and CWDM/DWDM metro links.
- Up to 4.25 Gb/s bi-directional links
- Hot-pluggable SFP footprint
- Temperature-stabilized DWDM-rated DFB laser transmitter
- 100 GHz ITU Grid, C-Band
- Wavelength controlled within ±0.1 nm over life and temperature
- Extended link budget with APD receiver technology
FWLF1634RL25: frequently asked questions
What is the Finisar FWLF1634RL25?
The FWLF1634RL25 is a Finisar SFP transceiver for DWDM 4.25G FC / 2.5G, APD rx (non-rate-select) at up to 4.25 Gb/s. Finisar is now part of Coherent Corp. (formerly II-VI), and the part number is unchanged. It is used for Gigabit Ethernet, 1/2/4G Fibre Channel SAN, SONET OC-48 / STM-16 and CWDM/DWDM metro links.
What is the maximum distance of the FWLF1634RL25?
The FWLF1634RL25 is specified for up to 80km over SMF. Long-reach optics may need an attenuator on short links; we can advise based on your link loss.
What is the optical power budget of the FWLF1634RL25?
Per the Finisar family datasheet, the FWLF1634RL25 transmits +2 to +5 dBm and has a receiver sensitivity of −28 dBm @2.5 Gb/s; −23 dBm @4.25 Gb/s (BER<10⁻¹²). Maximum receiver input is −9 dBm; damage threshold +6 dBm.
Does the FWLF1634RL25 support DDM / digital diagnostics?
Yes. Digital diagnostics per Finisar AN-2030; enhanced features per DWDM SFP MSA (A2h: laser current, temperature, Tx/Rx power). Your switch can read live temperature, voltage, laser bias and Tx/Rx power.
Which fiber and connector does the FWLF1634RL25 use?
The FWLF1634RL25 works at 1557.36nm (192.5THz, ITU ch25) over SMF. CWDM/DWDM optics must match the channel of your mux/demux port. Both ends of a link must use the same optical standard.
Will the FWLF1634RL25 work in my Cisco, Juniper, Arista or HPE switch?
The FWLF1634RL25 follows the SFP MSA, so it fits any matching port. It carries Finisar's own EEPROM programming; switches that check the module vendor may need a configuration setting or a vendor-branded optic. Send us your switch model and we confirm before dispatch.
FWLF1634RL25 vs FWLF1634RL17: what is the difference?
Both are in Finisar's FWLF1634RL family. They differ in wavelength (1557.36nm (192.5THz, ITU ch25) vs 1563.86nm (191.7THz, ITU ch17)). Pick the variant that matches your temperature, latch and wavelength needs.
What temperature range is the FWLF1634RL25 rated for?
The FWLF1634RL25 is a commercial-temperature part rated −5 to 70 °C. Choose an industrial (T) variant for outdoor or uncontrolled sites.
What does the FWLF1634RL25 part number mean?
The FWLF prefix marks Finisar's CWDM / DWDM wavelength-specific SFP family. The C letter in the suffix usually marks the commercial temperature grade. The remaining characters identify the optical design and build variant.
Is your FWLF1634RL25 genuine Finisar?
Yes. Next Gen Networks supplies original Finisar / Coherent modules, not third-party lookalikes or grey-market stock, and shares serial numbers on request.
What is the FWLF1634RL25 price in India and how do I order?
The Finisar FWLF1634RL25 price in India depends on quantity, delivery city and current stock. Next Gen Networks supplies it with a GST invoice (input tax credit ready) and pan-India dispatch from New Delhi. Send the part number, quantity and delivery city on WhatsApp +91-7827955775 or email Sales@nextgennetworks.in for a GST quote.
What power does the FWLF1634RL25 need?
It runs from 3.3 V (3.13–3.50 V) with power dissipation of 1.25 W max (Icc 325 mA typ).
Documents
NextGen datasheetPDF · specs, FAQ & buying guideManufacturer datasheet
Finisar / Coherent family datasheet
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