LTC4416 Datasheet, PDF (1/12 Pages) Linear Technology – 36V, Low Loss Dual PowerPath Controllers for Large PFETs

FEATURES
■ _{Designed Specifically to Drive Large and Small QG}
PFETs
■ _{Very Low Loss Replacement for Power Supply}
OR’ing Diodes
■ _{Wide Operating Voltage Range: 3.6V to 36V}
■ _{–40°C to 125°C Operating Temperature Range}
■ _{Reverse Battery Protection}
■ _{Automatic Switching Between DC Sources}
■ _{Low Quiescent Current: 35µA per Channel}
■ _{Load Current Sharing}
■ _{MOSFET Gate Protection Clamp}
■ _{Precision Input Control Comparators for Setting}
Switchover Threshold Points
■ _{Open-Drain Feedback Points for Customer Specified}
Hysteresis Control
■ _{Minimal External Components}
■ _{Space Saving 10-Lead MSOP Package}
U
APPLICATIO S
■ _{High Current PowerPath Switch}
■ _{Industrial and Automotive Applications}
■ _{Uninterruptible Power Supplies}
■ _{Logic Controlled Power Switch}
■ _{Battery Backup System}
■ _{Emergency Systems with Battery Backups}
, LT, LTc and LTM are registered trademarks of Linear Technology corporation.
PowerPath is a trademark of Linear Technology corporation.
All other trademarks are the property of their respective owners.
LTC4416/LTC4416-1
36V, Low Loss Dual
PowerPath Controllers for
Large PFETs
DESCRIPTIO
The LTC^®4416/LTC4416-1 control two sets of external
P-channel MOSFETs to create two near ideal diode functions
for power switchover circuits. This permits highly efficient
OR’ing of multiple power sources for extended battery life
and low self heating. When conducting, the voltage drop
across the MOSFET is typically 25mV. For applications with
a wall adapter or other auxiliary power source, the load is
automatically disconnected from the battery when the aux-
iliary source is connected.
The LTC4416 integrates two interconnected PowerPath^TM
controllers with soft switchover control. The “soft-off”
switchover permits the users to transfer between two dis-
similar voltages without excessive voltage undershoot (or
V_DROOP) in the output supply. The LTC4416/LTC4416-1 also
contain a “fast-on” feature that dramatically increases gate
drive current when the forward input voltage exceeds 25mV.
The LTC4416 “fast off” feature is engaged when the sense
voltage exceeds the input voltage by 25mV. The LTC4416-1
enables the fast off under the same conditions and when
the other external P-channel device is selected using the
enable pins.
The wide operating supply range supports operation from one
to eight Li-Ion cells in series. The low quiescent current (35µA
per channel) is independent of the load current. The gate driver
includes an internal voltage clamp for MOSFET protection.
The LTC4416/LTC4416-1 are available in low profile 10-lead
MSOP packages.
TYPICAL APPLICATIO
Automatic PowerPath Switchover
V1 = 12V (FAIL)
V1 = 13.5V (RESTORE) PRIMARY SUPPLY
V1
221k
SUP75P03_07
187k 24.9k
GND
V2
V2 = 10.8V
LTC4416
E1
V1
GND
G1
E2
V_S
H2
G2
H1
V2
BACKUP SUPPLY SUP75P03_07
V_S
4416 TA01
LTC4416 vs Schottky Diode
Forward Voltage Drop
8.0
cONSTANT
R_ON
3.6
LTc4416
cONSTANT
VOLTAGE
ScHOTTKY
DIODE
0
0.02
FORWARD VOLTAGE (V)
0.5
4416 TA01b
Under and Overvoltage Shutdown Operation
V_IN
221k
75k
V_TH2 WITH
HYSTERESIS
24.9k
GND
V_TH1 WITH
HYSTERESIS
187k 24.3k
182k LTC4416-1
H1
G1
E1
V1
GND
V_S
E2
V2
H2
G2
V_OUT
TO
LOAD
4416 TA01c
UV ENABLED AT 5V, V_IN RESTORED TO LOAD WHEN V_IN RISES TO 5.5V
OV ENABLED AT 13.5V, V_IN RESTORED TO LOAD WHEN V_IN FALLS TO 12V
4416fa