The STEF512PUR is an integrated dual electronic eFuse, designed to protect circuitry on the output from overcurrent and overvoltage events, in those applications requiring hot swap operation and in-rush current control.
The device embeds two independent electronic fuses, one for the 5 V rails and one for the 12 V rails. Thanks to the very low ON-resistance of the integrated power FETs, the voltage drop from the main supply to the load is very low during normal operation.
The startup time can be adjusted by the user for each eFuse, via two small soft-start capacitors, connected to the relevant pins.
In this way the inrush current at startup can be kept under control.
The maximum load current is precisely limited, by utilizing a sense FET topology, to factory-defined values (3 A for 5 V output and 4 A for 12 V output).
The device also provides precise overvoltage clamp for each channel, preventing the load being damaged from power supply failures, and undervoltage lockout (UVLO), assuring that the input voltage is above the minimum operating threshold, before the power device is turned on.
When an overload condition occurs, the STEF512PUR limits the output current to the predefined safe value. If the anomalous overload condition persists, the device goes into thermal shutdown, the internal switch is opened and the load disconnected from the power supply.
In the QFN10 package two current monitor pins are available, providing continuous information on the load current for each channel.