MaxLinear Introduces MxL745950 and MxL745951P High-Current eFuses for AI Infrastructure

MaxLinear has introduced two high-current eFuses for protecting and monitoring power paths in AI servers and rack-scale data centre infrastructure. The new MxL745950 and MxL745951P handle currents of up to 50 A and 60 A respectively, with integrated MOSFETs and protection functions for hot-swappable systems.

Both devices operate from power rails up to 16 V and are designed for equipment including accelerator trays, data centre switches, fan trays, power shelves and plug-in modules. The MxL745951P also adds digital telemetry and fault recording for systems requiring greater visibility into individual power domains.

Protecting High-Current Power Paths

As more compute, networking and supporting infrastructure is packed into an AI rack, power has to be distributed across a growing number of high-current loads. Individual cards and modules also need to be inserted, removed or isolated without allowing a fault or inrush event to affect the rest of the system.

The MxL745950 addresses these power paths with a 4 V to 16 V input range and current capability up to 50 A. Its integrated MOSFET has an on-resistance of 1 mΩ, limiting the voltage drop and power dissipated through the device at higher currents.

Current sensing and temperature monitoring are built in, alongside fault indication and programmable soft-start for controlling inrush current. Multiple devices can also operate in parallel where more than 50 A is required. Protection functions include undervoltage, overvoltage, overcurrent, short-circuit and overtemperature protection, as well as MOSFET fault diagnosis.

MxL745951P Adds Digital Telemetry

For power systems requiring more detailed monitoring, the MxL745951P increases current capability to 60 A and reduces integrated MOSFET on-resistance to 0.79 mΩ. Its operating input range extends from 2.9 V to 16 V.

The device adds PMBus and I²C interfaces, allowing system controllers to access telemetry for input and output voltage, current and power, along with input energy. Current monitoring accuracy is specified at ±1%.

MaxLinear has also included configurable protection thresholds and timers, non-volatile configuration storage and black-box fault recording. The latter provides stored information about fault events that can be used when investigating problems elsewhere in the power system.

The MxL745951P is stackable for higher-current designs, with active current balancing during start-up and steady-state operation.

Designed for AI and Data Centre Hardware

The two eFuses give designers different levels of monitoring and control within the same 16 V class. The MxL745950 provides analog monitoring and protection for power paths up to 50 A, while the MxL745951P combines 60 A capability with digital telemetry, configuration and fault recording.

MaxLinear supplies the MxL745950 in a 5 × 5 mm LGA-32 package. The MxL745951P uses a 5 × 4.5 mm VQFN-26L package.

Target applications include AI servers, accelerator trays, networking equipment, data centre switches and routers, fan trays, power shelves and other rack-level infrastructure.

Both devices are sampling now, with volume production expected in Q4 2026.

Learn more and read the original announcement at the MaxLinear website.

Technology Overview

An electronic fuse, or eFuse, uses semiconductor switching and control circuitry to protect a power path electronically. Unlike a conventional fuse that must be replaced after it opens, an eFuse can monitor operating conditions and disconnect a load when a fault such as excessive current, voltage or temperature is detected.

In hot-swappable systems, an eFuse can also control inrush current as a board or module is connected to a live power rail.

Frequently Asked Questions

What are the MaxLinear MxL745950 and MxL745951P?

The MxL745950 and MxL745951P are high-current electronic fuses designed for power protection in AI and data centre infrastructure. The MxL745950 supports up to 50 A, while the MxL745951P supports up to 60 A.

What is the difference between the MxL745950 and MxL745951P?

The MxL745950 provides analog current sensing, temperature monitoring and fault indication. The MxL745951P adds PMBus/I²C connectivity, digital power telemetry, configurable protection, non-volatile storage and black-box fault recording.

Can the MaxLinear eFuses be used for currents above 60 A?

Both devices support higher-current implementations through parallel operation. The MxL745951P also provides active current balancing during start-up and steady-state operation.