RS31323 18V Power MUX for Efficient Power Path Management

The RS31323 is a high-performance 18V Power MUX designed to provide intelligent power path management for systems requiring seamless switching between multiple power sources. Featuring integrated back-to-back MOSFETs, priority-based source selection, and low R_DS(ON) power paths, the RS31323 delivers efficient power transfer while protecting against reverse current flow.

Supporting an operating voltage range of 4V to 18V and delivering up to 4.5A continuous output current, the RS31323 combines fast source switchover, low operating current, and comprehensive protection features in a compact 2 × 2.5 mm VQFN-12 package. Optimized for primary and backup power architectures, the RS31323 simplifies system design while improving efficiency and overall system reliability.

Intelligent Power Source Selection

Many electronic systems rely on multiple power sources, including batteries, AC adapters, USB power, and redundant supply rails. The RS31323 automatically manages these sources using priority-based input selection, ensuring the preferred input powers the load while seamlessly transitioning to an alternate source whenever required.

Fast source switchover minimizes output voltage droop, reducing the amount of output capacitance required while maintaining uninterrupted operation of downstream circuitry.

Individual enable inputs provide additional flexibility for system startup sequencing, battery management, and application-specific power control.

Optimized for Efficient Power Delivery

The RS31323 integrates low R_DS(ON) back-to-back MOSFETs to minimize conduction losses while preventing reverse current flow between power sources.

Key performance advantages include:

• Wide 4V to 18V operating voltage range
• Up to 4.5A continuous output current
• Low 40mΩ R_DS(ON) on Channel 1
• Low 64mΩ R_DS(ON) on Channel 2
• Fast reverse current detection and recovery
• Low 330µA operating quiescent current
• Low 10µA shutdown current

These features help improve overall power conversion efficiency while reducing thermal dissipation in compact designs.

Integrated Monitoring and Protection

The RS31323 combines intelligent source selection with integrated protection features to simplify system-level power management.

Integrated features include:

• Priority-based source selection
• Individual enable inputs
• Adjustable overcurrent protection
• Reverse current blocking
• Fault indication output
• Input undervoltage protection (UVP)
• Input overvoltage protection (OVP)
• Overtemperature protection

Together, these capabilities help protect both the power sources and downstream electronics while reducing the need for additional external circuitry.

Compact Solution for Primary and Backup Power Systems

The RS31323 integrates intelligent power path management into a compact 2 × 2.5 mm VQFN-12 package, making it well suited for applications where board space and efficiency are equally important.

Typical applications include:

• Battery-powered devices
• Battery management systems
• Primary and backup power systems
• Power path management
• Redundant power supplies
• Industrial control systems
• Embedded computing
• Surveillance equipment
• Telematics

Its combination of compact size, efficient power delivery, and integrated protection makes the RS31323 an excellent solution for systems requiring reliable source selection and uninterrupted operation.

Smart Power. Seamless Switching.

The RS31323 combines efficient power delivery, intelligent source selection, and comprehensive system protection into a highly integrated Power MUX solution. Integrated low R_DS(ON) MOSFETs, fast source switchover, reverse current protection, and configurable overcurrent protection help designers build compact, reliable, and energy-efficient power systems with fewer external components.

As part of Reed Semiconductor’s Power MUX family, the RS31323 delivers Smart Power. Seamless Switching. Whether selecting between battery and external power, managing redundant power rails, or optimizing industrial power architectures, the RS31323 provides an efficient and dependable solution for modern power path management.