STEF033 Datasheet, PDF (1/25 Pages) STMicroelectronics – Electronic fuse for 3.3 V line

STEF033
Electronic fuse for 3.3 V line
DFN10 (3 x 3 mm)
Flip Chip 9
Features
• Continuous current typ.: 3.6 A (DFN), 2.5 A
(Flip Chip)
• N-channel on resistance (typ): 40 mΩ (DFN),
25 mΩ (Flip Chip)
• Enable/Fault functions
• Output clamp voltage (typ): 4.5 V
• Undervoltage lockout
• Short-circuit limit
• Overload current limit
• Controlled output voltage ramp
• Thermal latch (typ): 160 °C
• Uses tiny capacitors
• Latching and auto-retry versions
• Operative junction temp. - 40 °C to 125 °C
• Available in DFN10 3x3 and Flip Chip 9 bumps
Applications
• Hard disk drives
• Solid state drives (SSD)
• Hard disk and SSD arrays
• Computer
• DVD and Blu-Ray disc drivers
Datasheet - production data
Description
The STEF033 is an integrated electronic fuse
optimized for monitoring output current and the
input voltage. Connected in series to the 3.3 V
rail, it is able to protect the electronic circuitry on
its output from overcurrent and overvoltage. The
STEF033 has controlled delay and turn-on time.
When an overload condition occurs, the device
limits the output current to a predefined safe
value. If the anomalous overload condition
persists, it goes into an open state, disconnecting
the load from the power supply. If a continuous
short-circuit is present on the board, when the
power is re-applied the E-fuse initially limits the
output current to a safe value and then goes
again into the open state. The voltage clamping
circuit prevents the output voltage from exceeding
a fixed value, if the input voltage goes beyond this
threshold. The device is equipped with a thermal
protection circuit. Intervention of thermal
protection is signaled to the board-monitoring
circuits through an appropriate signal on the Fault
pin. Unlike mechanical fuses, which must be
physically replaced after a single event, the E-
fuse does not degrade in its performances
following short-circuit/thermal protection
intervention and is reset either by re-cycling the
supply voltage or using the appropriate Enable
pin. The STEF033 is also available in an auto-
retry version; in case of thermal fault it
automatically attempts to re-apply power to the
load when the die temperature returns to a safe
value.
January 2015
This is information on a product in full production.
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