LTC4357_15 Datasheet, PDF (1/14 Pages) Linear Technology – Positive High Voltage Ideal Diode Controller

Features
n _{Reduces Power Dissipation by Replacing a Power}
Schottky Diode with an N-Channel MOSFET
n _{0.5µs Turn-Off Time Limits Peak Fault Current}
n _{Wide Operating Voltage Range: 9V to 80V}
n _{Smooth Switchover without Oscillation}
n _{No Reverse DC Current}
n _{Available in 6-Lead (2mm × 3mm) DFN and}
8-Lead MSOP Packages
Applications
n _{N + 1 Redundant Power Supplies}
n _{High Availability Systems}
n _{AdvancedTCA Systems}
n _{Telecom Infrastructure}
n _{Automotive Systems}
LTC4357
Positive High Voltage
Ideal Diode Controller
Description
The LTC^®4357 is a positive high voltage ideal diode control-
ler that drives an external N-channel MOSFET to replace a
Schottky diode. When used in diode-OR and high current
diode applications, the LTC4357 reduces power consump-
tion, heat dissipation, voltage loss and PC board area.
The LTC4357 easily ORs power sources to increase total
system reliability. In diode-OR applications, the LTC4357
controls the forward voltage drop across the MOSFET to
ensure smooth current transfer from one path to the other
without oscillation. If the power source fails or is shorted,
a fast turn-off minimizes reverse current transients.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
Hot Swap is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Typical Application
48V, 10A Diode-OR
V_INA
FDB3632
48V
IN
GATE
OUT
LTC4357
V_DD
GND
V_OUT TO LOAD
V_INB
FDB3632
48V
IN
GATE
OUT
LTC4357
GND
V_DD
4357 TA01
*SEE FIGURES 2 AND 3 FOR ADDITIONAL OPTIONAL COMPONENTS
Power Dissipation vs Load Current
6
5
DIODE (MBR10100)
4
3
POWER
SAVED
2
1
FET (FDB3632)
0
0
2
4
6
8
10
CURRENT (A)
4357 TA01b
4357fd