Fuse principle

A fuse is a component that protects a device by melting itself to cut off the circuit when excessive current flows in an electrical circuit.
In other words, if the fuse itself blows, the electrical equipment cannot be used again unless the fuse itself is replaced.

Principle of eFuse

Below is a schematic diagram of an eFuse. A current limit (ILIMIT) can be set with an external resistor value for the eFuse.

Then, when overcurrent flows, the current flows at the current limit value (ILIMIT), and when the temperature reaches the specified value (thermal shutdown temperature), the internal MOSFET is turned off. In this way, the eFuse turns the internal MOSFET on and off to break the circuit, so there is no need to replace parts even if overcurrent flows.

protective function

・Current limit function
The current limit value can be set by the resistance value connected to     the ILIMIT (or Current Limit) pin, and the current flowing through the internal MOSFET is limited by the set current value.


・Overheating protection function
A built-in temperature sensing circuit senses the temperature of the internal MOSFET die. When the temperature reaches a specified value (such as 175°C in the datasheet), the device shuts down.


・Overvoltage protection function
It monitors the output voltage and reduces the gate drive of the internal MOSFET to limit the output when the input voltage exceeds the clamp voltage.

・Backflow prevention function (Option)
It protects against reverse current events due to power supply malfunction and noise injection into the input voltage rail.

Status detection function

・Fault/FLAG output

・Enable input

・Current monitoring

Other functions

・Adjustable output slew rate
Output rise slew rate can be adjusted.

・Latch (Re-input the control signal and return)
・Autoretry
You can choose the latched or auto-wake version of wake-up after shutdown.

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