RS31210

RS31210 5V, 5A eFuse for Compact Power Path Protection

Modern 5V power rails require more than a simple fuse to protect valuable electronics from overloads, short circuits, startup inrush current, and fault conditions. The RS31210 is a compact, integrated 5V eFuse that combines an ultra-low-loss 25mΩ MOSFET, programmable current limiting, adjustable undervoltage lockout (UVLO), and controlled startup into a single 3 × 3 mm VSON package.

Designed for server auxiliary rails, PCIe cards, SSDs, embedded systems, industrial electronics, and adapter-powered equipment, the RS31210 provides reliable power-path protection while minimizing board space, component count, and power dissipation.

Unlike traditional resettable fuses or discrete MOSFET protection circuits, the RS31210 actively monitors system conditions to protect downstream circuitry while allowing designers to optimize startup behavior and fault response for each application.

Intelligent Protection for 5V Power Rails

The RS31210 protects downstream loads from common electrical faults that can damage sensitive electronics or disrupt system operation.

Integrated protection includes:

• Adjustable 2A to 5A current limit
• Fixed 6.1V overvoltage clamp
• Overtemperature protection
• Programmable undervoltage lockout (UVLO)
• Adjustable output slew rate for controlled startup
• Enable input for system power sequencing

Together, these features help reduce stress on power supplies while protecting downstream circuitry during startup, overload, and fault conditions.

Minimize Power Loss

The integrated 25mΩ pass MOSFET minimizes voltage drop and conduction losses compared to traditional protection circuits, improving overall system efficiency while reducing heat generation.

Because the MOSFET is fully integrated, designers can eliminate numerous external components, simplifying PCB layout and reducing total solution size.

Programmable Startup and Inrush Control

Large output capacitors often create high inrush currents during startup. The RS31210 allows designers to control startup behavior using an external capacitor connected to the dV/dt pin.

Programmable output slew-rate control:

• Limits inrush current
• Reduces stress on upstream power supplies
• Improves hot-plug reliability
• Enables clean system power sequencing

Combined with the adjustable current limit and UVLO threshold, designers can easily optimize startup performance for a wide variety of applications.

Optimized for Space-Constrained Designs

The RS31210 is housed in a compact 3 × 3 mm VSON-10 package, making it ideal for high-density electronics where PCB area is limited.

Typical applications include:

• PCI and PCIe expansion cards
• Solid-state drives (SSD)
• Hard disk drives (HDD)
• Server auxiliary power rails
• Embedded computing
• Industrial control systems
• Adapter-powered electronics
• Networking equipment

Its compact footprint allows designers to add comprehensive power protection without sacrificing valuable board space.

Choose the Right Reed Semiconductor eFuse

The RS31210 is part of Reed Semiconductor’s expanding family of intelligent circuit protection devices.

Whether protecting compact peripheral power rails or high-current AI accelerator systems, Reed Semiconductor provides intelligent eFuse solutions for virtually every stage of the power distribution network.

Why Choose the RS31210?

The RS31210 combines programmable protection, low conduction losses, and minimal PCB footprint into a single integrated solution. With adjustable current limiting, controlled startup, programmable UVLO, and comprehensive fault protection, it simplifies power-path design while improving system reliability across a broad range of 5V applications.