25G SFP28 BiDi Optical Transceiver Module
Product Overview
The Apex 25G SFP28 BiDi module carries a 25 Gigabit link over a single strand of fiber. The transmitter runs at 1270nm and the receiver at 1330nm, so a working link uses two matched parts: one 1270nm TX / 1330nm RX unit and its partner at 1330nm TX / 1270nm RX.
25G is the lane rate inside 100G and the port speed on 5G fronthaul, top of rack and enterprise access equipment, and it is often installed where fiber is the scarce part, such as a fronthaul route from a baseband unit to a remote radio site or a duct with one spare strand. A BiDi link uses that strand for both directions and leaves the second fiber free for a future service.
Every unit is burnt in and tested for optical power, extinction ratio and error rate, supports DDM with live optical readings, and is coded for the platform you name. Reach options cover 10km, 20km and 40km over single mode fiber, and industrial temperature versions are available for outdoor cabinets and unheated shelters.
Key Features
- 25.78Gbps line rate for 25G Ethernet and CPRI / eCPRI fronthaul
- SFP28 MSA hot pluggable package, single fiber BiDi design
- 1270nm transmitter / 1330nm receiver, matched partner module required
- Reach options of 10km, 20km and 40km over single mode fiber
- Simplex LC interface, one fiber strand per link
- Digital Diagnostic Monitoring (DDM/DOM) with live optical readings
- Low power consumption, single 3.3V supply
- Coded for the switch, fronthaul or routing platform before shipment
Technical Specifications
| Specification | Detail |
|---|
| Part Number | APX-SFP28-25G-xxKM-BIDI (xx = reach) |
| Manufacturer | Apex |
| Data Rate | 25.78Gbps (also 24.33Gbps for CPRI options 7 and 8) |
| Form Factor | SFP28, hot pluggable |
| Optical Technology | BiDi, single fiber bidirectional |
| Wavelength | 1270nm TX / 1330nm RX (partner unit 1330nm TX / 1270nm RX) |
| Reach Options | 10km, 20km, 40km over SMF |
| Fiber Type | Single Mode Fiber (SMF) |
| Connector Type | LC simplex |
| Transmitter | DFB laser, uncooled |
| DDM / DOM | Supported |
| Supply Voltage | 3.3V |
| Compliance | SFP28 MSA, IEEE 802.3by, RoHS |
| Temperature | 0 to 70C commercial, -40 to 85C industrial on request |
Ordering Options
Family options are listed below as plain text so they can be copied into an RFQ or a spreadsheet.
| Ordering code | Wavelength pair | Reach | Interface |
|---|
| APX-SFP28-25G-10km-BIDI-27 | 1270nm TX / 1330nm RX | 10km | LC simplex |
| APX-SFP28-25G-10km-BIDI-33 | 1330nm TX / 1270nm RX | 10km | LC simplex |
| APX-SFP28-25G-20km-BIDI-27 | 1270nm TX / 1330nm RX | 20km | LC simplex |
| APX-SFP28-25G-20km-BIDI-33 | 1330nm TX / 1270nm RX | 20km | LC simplex |
| APX-SFP28-25G-40km-BIDI-27 | 1270nm TX / 1330nm RX | 40km | LC simplex |
| APX-SFP28-25G-40km-BIDI-33 | 1330nm TX / 1270nm RX | 40km | LC simplex |
Applications
5G Fronthaul on a Single Fiber
Carries the 25G fronthaul link between baseband and radio equipment over one strand, which suits routes where only a single fiber reaches the site.
Access and Metro 25G Uplinks
Delivers 25G to a street cabinet, aggregation point or customer where the spare fiber count is limited and pulling more is not economic.
Enterprise and Industrial 25G
Upgrades a switch or server uplink to 25G on existing fiber, with industrial temperature versions for outdoor enclosures and plants.
Compatibility
25G BiDi modules are coded to the host platform you specify, including 25G switches, fronthaul equipment and routers, and are tested on live ports before shipment. Fronthaul links often add timing and latency requirements to the port, so we confirm the host role and the CPRI or Ethernet line rate at the same time as we quote the pair.
Related Products
Frequently Asked Questions
How do 25G BiDi pairs work?
Each module transmits on one wavelength and receives on the other, 1270nm and 1330nm. Two identical units cannot see each other, so a link is built from one 1270/1330 and one 1330/1270 part, shipped and labelled as a pair.
Which reach do I need for 25G fronthaul?
10km covers most urban fronthaul runs, 20km and 40km cover longer routes to remote sites. We check the measured span and loss budget before recommending the grade.
Does the module support fronthaul rates as well as 25G Ethernet?
Yes. The line rate covers 25G Ethernet and the 24.33Gbps CPRI options used on fronthaul ports. Tell us the host and the rate and we confirm the coding.
Are industrial temperature versions available?
Yes. Commercial 0 to 70C is standard and industrial -40 to 85C versions are available for outdoor cabinets and unheated shelters.
Why Choose Apex
- Optical engineering support and supply from 1.25G to 800G, including single fiber 25G and 100G lines.
- Matched BiDi pairs are shipped and labelled together so installation is unambiguous.
- Every module is tested for optical power, extinction ratio and error rate before shipment.
- Backed by a 3 year warranty and technical support before and after the sale.
