100G QSFP28 to 25G SFP28 Adapter (QSA) Module

• Enables compatible 25G SFP28 connectivity through QSFP28 ports
• Supports one independent duplex channel at up to 25Gbps
• Supports 10Gbps and 5Gbps operation where supported by the host platform
• Compliant with SFF-8665 and SFF-8432 specifications
• Plug-and-play installation for simplified network deployment
• Single +3.3V power architecture through the host interface
• 100-ohm differential impedance design
• Precision process control for minimized pair-to-pair skew
• Low insertion loss and low crosstalk
• Optimized signal integrity for high-speed electrical transmission
• All-metal zinc-alloy housing for enhanced EMI performance

• 100G to 25G network migration
• 25G SFP28 transceiver deployment through compatible QSFP28 ports
• Data center network upgrades
• Network expansion and port utilization
• Enterprise network infrastructure
• Optical network modernization
• Data center interconnects (DCI)
• High-performance computing (HPC)
• Hybrid cloud infrastructure
• Mixed-speed network environments

OEM and customized QSA solutions are available for network equipment manufacturers, system integrators, distributors, and large-scale data center deployments. Customization and production support may include product labeling, branding, packaging, mechanical requirements, and project-specific compatibility requirements.

For equipment-specific applications, customers can provide the target switch or router model, required operating speed, intended SFP28 module or cable type, and deployment quantity for compatibility evaluation. This helps ensure that the adapter is appropriate for the intended host platform and network configuration.

Does this QSA convert a 100G signal directly into a 25G signal?

The QSA primarily provides interface adaptation between a QSFP28 port and an SFP28 interface. It is not intended to function as a standalone active 100G-to-25G protocol converter. The host equipment must support the required breakout, port-mode, or lower-speed operating configuration for the adapter to function correctly.

Can the adapter support both 25G and 10G SFP modules?

The adapter supports a single independent duplex channel at 25Gbps and can also support 10Gbps and 5Gbps data rates where these operating modes are supported by the host equipment and connected module. Actual supported speeds should therefore be confirmed against the specific switch or router.

Why is a 100-ohm differential impedance important?

High-speed electrical signals are sensitive to impedance discontinuities. Maintaining a controlled 100-ohm differential impedance helps reduce reflections and signal distortion as electrical signals pass between the QSFP28 host interface and SFP28 device, contributing to more reliable high-speed transmission.

Can the QSA be used with any QSFP28 switch?

Not necessarily. Although the adapter follows relevant SFF interface specifications, the host equipment must support the required operating mode and recognize the connected SFP28 device. Vendor-specific compatibility and port configuration should be checked before deployment.

What is the advantage of the all-metal housing?

The zinc-alloy housing provides mechanical protection while also helping shield the high-speed electrical interface against electromagnetic interference. This can be particularly beneficial in dense data center environments where multiple high-speed interfaces operate close together.

When is a QSA useful during network migration?

A QSA can be useful when a network is transitioning to higher-speed equipment but still needs to deploy existing 25G SFP28 resources. Instead of replacing all equipment and optical components at once, compatible QSFP28 ports can potentially accommodate 25G SFP28 connectivity, helping provide a more gradual migration path.