Fuses protect and reset power supply lines

While conventional fuses physically break the electrical link to the circuit they are protecting, eFuses are resettable, providing further protection features such as a highly accurate over-current limit, over-voltage protection, and over-temperature protection in addition to short-circuit protection. Compared to polymeric positive temperature co-efficient (PPTC) devices that are also resettable, they react significantly faster, says the company, can be reset directly via an external logic signal, and retain their low on-resistance even after multiple trip events.

There are three categories in the series: no over-voltage protection, 5V (V_OVC = 6.04V), and 12V (V_OVC = 15.1V). Each over-voltage category is also offered in auto-retry or latched options for the response after a fault event. The status of the latch type is recovered by the application of an external signal, while the auto-retry is capable of re-enabling its output a

The integrated fast-trip comparator can switch off the output typically within 150ns. An external capacitor can be included to reduce inrush current by setting a turn-on slew-rate at the output as required. Provision is also made to support an external N-channel MOSFET for reverse-current blocking protection.

Typical applications include the supply lines to cameras, cordless cleaner and power tools, cleaning robots, server, smart speaker, thermostats and wireless chargers.

The devices are offered in a 3.0 x 3.0mm WSON10B package that is 0.75mm thick. They offer a typical R_ON of 28mΩ and an over-current limit accuracy if ±11%. Input voltages of 4.4 to 18.0V are supported and output currents can be up to 5.0A.

The fuses are certified to IEC 62368-1.