Features
• 5 V and 12 V channels into one chip
• 25 V absolute maximum input voltage
• Precise output overvoltage clamp
• Fixed overcurrent protection for both channels
• Reverse current protection on 5 V channel
• Thermal protection
• Available in auto-retry version
• Input undervoltage lockout
• Adjustable output voltage slew rate
• Integrated 45 mΩ power MOSFETs
• SAS disable pin
• Current monitor pin selection
• Current monitor output in a single pin for both rails
• DFN10 (2 x 3 mm) package

Applications
• HD and SSD
• Hard disk arrays and NAS
• Hot plug protections

Description
The STEF512SRX is an integrated dual electronic fuse, designed to protect circuitry
on the output from overcurrent and overvoltage events, in those applications
requiring hot swap operation and inrush current control.
The device embeds two electronic fuses, one for the 5 V rail and one for the 12 V rail.
Thanks to the very low on-resistance of the integrated power MOSFETs, the voltage
drop from the main supply to the load is very low during normal operation.
The 5 V channel provides a reverse blocking feature, preventing current flow to the
input in case of brown-out or shutdown.
The start-up time is internally controlled by a dedicated slew rate circuit. 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.
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 is turned on.
When an overload condition occurs, the STEF512SRX 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 is disconnected
from the power supply.
Load current on each channel can be accurately monitored by reading the signal on
the IMON_5/12 pin.