Hot Swap Smart Fuses

onsemi Hot Swap smart fuses are advanced, electronically resettable in-line protection devices designed for high-current 12 V systems such as servers, storage arrays, and base stations. These fuses integrate a low R_DS(on) NMOS FET (as low as 0.65 mΩ), a high-performance hot-swap controller, and in some models, non-volatile memory (NVM), all within a compact 5 mm x 5 mm QFN32 package. With continuous current ratings up to 50 A and peak capabilities reaching 80 A, these smart fuses offer programmable soft-start, multi-level current limiting, and fast short-circuit protection to ensure safe and efficient power delivery.

The smart fuse family supports parallel operation for higher current applications and includes features such as analog current and temperature monitoring, programmable overcurrent alerts, and fault diagnostics. The NCP81428 variant adds PMBus 1.4 compliance for digital configuration and telemetry, making it ideal for intelligent power systems. These devices are engineered for rugged environments with operating temperatures from -40°C to +125°C and built-in ESD protection. Whether used in standalone or multi-phase configurations, onsemi Hot Swap smart fuses deliver reliable, resettable protection for today's demanding electronic systems.