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dc1506af
DEMO MANUAL DC1506A
DESCRIPTION
LTC4361 Overvoltage/
Overcurrent Protection
Controller
Demonstration circuit DC1506A features the LTC
®
4361
an overvoltage/overcurrent protection controller that
safeguards 2.5V to 5.5V systems from input supply over-
voltage. The LTC4361 is designed for portable devices with
multiple power supply options including wall adapters, car
battery adapters and USB ports.
The LTC4361 controls an external N-channel MOSFET in
series with the input power supply. During overvoltage
transients, the LTC4361 turns off the MOSFET within 1µs,
isolating downstream components from the input supply.
Inductive cable transients are absorbed by the MOSFET
and load capacitance. In most applications, the LTC4361
provides protection from transients up to 80V without
requiring transient voltage suppressors or other external
components.
The LTC4361 has a delayed start-up and adjustable
dV/dt ramp-up for inrush current limiting. A
PWRGD
pin
provides power good monitoring for V
IN
. The LTC4361
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Figure 1. Demonstration Circuit 1506A
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 LTC4361 automatically restarts with a start-up delay.
After an overcurrent fault, the LTC4361-1 remains off
while the LTC4361-2 automatically restarts after a 130ms
start-up delay.
DC1506A demonstrates three protection schemes selected
with a jumper: (A) overvoltage and overcurrent protec-
tion, (B) overvoltage, overcurrent, and negative voltage
protection, and (C) overvoltage, overcurrent, negative
voltage, and reverse current protection. Each option has
ON control, an output LED and can be applied to a USB
protected output.
Design files for this circuit board are available at
1506a FO1
