LTC4352 Datasheet, PDF (1/16 Pages) Linear Technology – Low Voltage Ideal Diode Controller with Monitoring

FEATURES
n _{Low Loss Replacement for Power Diode}
n _{Controls N-Channel MOSFET}
n _{0V to 18V Supply ORing or Holdup}
n _{0.5μs Turn-On and Turn-Off Time}
n _{Undervoltage and Overvoltage Protection}
n _{Open MOSFET Detect}
n _{Status and Fault Outputs}
n _{Hot Swappable}
n _{Reverse Current Enable Input}
n _{12-Pin MSOP and DFN (3mm × 3mm) Packages}
APPLICATIONS
n _{Redundant Power Supplies}
n _{Supply Holdup}
n _{Telecom Infrastructure}
n _{Computer Systems and Servers}
LTC4352
Low Voltage Ideal Diode
Controller with Monitoring
DESCRIPTION
The LTC^®4352 creates a near-ideal diode using an external
N-channel MOSFET. It replaces a high power Schottky
diode and the associated heat sink, saving power and
board area. The ideal diode function permits low loss
power ORing and supply holdup applications.
The LTC4352 regulates the forward voltage drop across
the MOSFET to ensure smooth current transfer in diode-OR
applications. A fast turn-on reduces the load voltage droop
during supply switch-over. If the input supply fails or is
shorted, a fast turn-off minimizes reverse currents.
The controller operates with supplies from 2.9V to 18V.
For lower voltages, an external supply is needed at the
V_CC pin. Power passage is disabled during undervoltage
or overvoltage conditions. The controller also features an
open MOSFET detect circuit that flags excessive voltage
drop across the pass transistor in the on state. A REV pin
enables reverse current, overriding the diode behavior
when desired.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
2.9V TO 18V
2.9V to 18V Ideal Diode
0.1μF*
Si7336ADP
TO LOAD
0.1μF
CPO SOURCE V_IN GATE OUT
V_CC
STATUS
UV
LTC4352
OV
FAULT
REV
GND
4352 TA01
*OPTIONAL
MOSFET ON
STATUS
FAULT
Power Dissipation vs Load Current
4.0
3.5
3.0
DIODE (SBG1025L)
2.5
2.0
1.5
POWER
SAVED
1.0
0.5
0
0
MOSFET (Si7336ADP)
2
4
6
8
10
LOAD CURRENT (A)
4352 TA01b
4352f
1