Fuses protect and reset power supply lines
Multiple protection options are afforded with eFuse ICs from Toshiba Electronics Europe. The company introduces six products in the TCKE8xx series for low voltage applications.
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 (VOVC = 6.04V), and 12V (VOVC = 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 RON 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.