LTC4362-2_15 Datasheet, PDF (1/14 Pages) Linear Technology – 1.2A Overvoltage/ Overcurrent Protector

FEATURES
n _{2.5V to 5.5V Operation}
n _{Overvoltage Protection Up to 28V}
n _{Internal 40mΩ N-Channel MOSFET and 31mΩ RSENSE}
n _{Avalanche Rated MOSFET Requires No Input}
Capacitor or TVS for Most Applications
n _{<1μs Overvoltage Turn-Off, Gentle Shutdown}
n _{2% Accurate 5.8V Overvoltage Threshold}
n _{20% Accurate 1.5A Overcurrent Threshold}
n _{Input Withstands Up to ±25kV HBM ESD with}
≥1μF C_OUT
n _{Controlled Power-Up dV/dt Limits Inrush Current}
n _{Reverse Voltage Protection Driver}
n _{Low Current Shutdown}
n _{Latchoff (LTC4362-1) or Auto-Retry (LTC4362-2)}
After Overcurrent
n _{Available in 8-Lead DFN 2mm × 3mm Package}
APPLICATIONS
n _{USB Protection}
n _{Handheld Computers}
n _{Cell/Smart Phones}
n _{MP3/MP4 Players}
n _{Digital Cameras}
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
ThinSOT, PowerPath and Hot Swap are trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
LTC4362-1/LTC4362-2
1.2A Overvoltage/
Overcurrent Protector
DESCRIPTION
The LTC^®4362 monolithic overvoltage/overcurrent protec-
tor safeguards 2.5V to 5.5V systems from power supply
overvoltage. It is designed for portable devices with multiple
power supply options including wall adaptors, car battery
adaptors and USB ports.
The LTC4362 controls an internal 40mΩ N-channel MOSFET
in series with the input power supply. During overvoltage
transients, the LTC4362 turns off the MOSFET within 1μs,
isolating downstream components from the input supply.
In most applications, the LTC4362 rides through induc-
tive cable transients without requiring transient voltage
suppressors or other external components. An internal
current sense resistor is used to implement overcurrent
protection.
The LTC4362 has a delayed start-up at plug-in and con-
trolled dV/dt ramp-up for inrush current limiting. A PWRGD
pin provides power good monitoring for V_IN. The LTC4362
features a soft-shutdown controlled by the ON pin and
drives an optional external P-channel MOSFET for negative
voltage protection. Following an overvoltage condition, the
LTC4362 automatically restarts with a 130ms delay. After
an overcurrent fault, the LTC4362-1 remains off while the
LTC4362-2 automatically restarts after a 130ms delay.
TYPICAL APPLICATION
Protection from Overvoltage and Overcurrent
V_IN
5V
IN
OUT
V_OUT
5V
0.5A
LTC4362
C_OUT
ON PWRGD
GND
436212 TA01a
Output Protected from Overvoltage at Input
V_IN
V_IN, V_OUT
5V/DIV
V_OUT
C_OUT = 10μF
0.2μs/DIV
436212 TA01b
436212fa
1