eFuses and hot-swap ICs

Hot-swap power management ICs are designed to control and protect electronic loads, reducing ownership costs of electronic devices and appliances during production and in the field.

They are ideal for all applications that need to perform hot-plug/hot-swap operations or require a high level of flexibility and reliability. In such applications, a complete and accurate control of the inrush current during startup/hot plug, along with overcurrent/overvoltage protections are crucial and can make the difference in terms of final cost of maintenance and cost of quality.

Compared to traditional protection devices, hot-swap power management ICs enable more versatile and simpler programming of protection parameters, such as overcurrent threshold and start-up time. Thanks to their Enable/fault pins, hot-swap power management ICs can be remotely reset after a fault, which helps to drastically reduce the number of false-faults and equipment downtime.

Within its hot-swap power management family, ST offers three main kinds of hot-swap controllers:

  • Electronic fuses (eFuses): they can replace larger conventional fuses or other protection devices such as resettable PTC fuses. Housed in small plastic packages, such as DFN and Flip-chip, they integrate a control logic and a power switch. E-fuses provide overvoltage and overcurrent protection and programmable soft-start time. Typical applications are HDD/SSD arrays and servers as well as industrial and network hot-swap boards.
  • DC Power breakers: they provide continuous monitoring of the input power and interrupt the circuit in case of anomalous power consumption. The power limit is adjustable by the user. Used in home appliances and white goods, they optimize the design of power distribution systems, and simplify the certification flow to comply with international safety regulations.
  • Other hot-swap ICs, such as programmable current limiters and controllers for external MOSFETs. They allow maximum configuration flexibility, and provide protection to high-power DC rails.

eFuse pdf

STPW12, the first electronic power breaker for 12 V bus keeps home appliances in check