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dc1505af
DEMO MANUAL DC1505A
DESCRIPTION
LTC4360 Overvoltage
Protection Controller
Demonstration circuit DC1505A features the LTC
®
4360 an
overvoltage protection controller that safeguards 2.5V to
5.5V systems from input supply overvoltage. The LTC4360
is designed for portable devices with multiple power sup-
ply options including wall adapters, car battery adapters
and USB ports.
The LTC4360 controls an external N-channel MOSFET in
series with the input power supply. During overvoltage
transients, the LTC4360 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 LTC4360
provides protection from transients up to 80V without
requiring transient voltage suppressors or other external
components.
The LTC4360 has a delayed start-up and adjustable
dV/dt ramp-up for inrush current limiting. A
PWRGD
pin
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 1505A
provides power good monitoring for V
IN
. The LTC4360-1
features a soft shutdown controlled by the
ON
pin. The
LTC4360-2 has a GATEP pin that drives an optional ex-
ternal P-channel MOSFET for negative voltage protection.
Following an overvoltage condition, the LTC4360 automati-
cally restarts with a start-up delay.
DC1505A demonstrates three protection schemes selected
with a jumper: (A) overvoltage protection, (B) overvoltage
and negative voltage protection, and (C) overvoltage, nega-
tive voltage, and reverse current protection. Each option
has an output LED and can be applied to a USB protected
output. Protection (A) features the LTC4360-1 with ON
control. Protection (B) and (C) feature the LTC4360-2 and
a P-channel MOSFET driven by GATEP.
Design files for this circuit board are available at
1505a FO1
