Features
• 5 V and 12 V channels into one chip
• Output over voltage clamp
• Fixed current limit : 3 A on 5 V, 4 A on 12 V
• Latched-off thermal protection
• Input undervoltage lockout
• Adjustable output voltage slew rate for each channel
• Integrated 40 mΩ Power FETs
• SAS disable pin
• Current monitor output
• QFN10-2x3 package

Applications
• HD and SSD drives
• Set-top boxes
• DVD and Blu-ray disc drivers

Description
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.