Datasheet
LTC4359
5
4359fa
For more information www.linear.com/LTC4359
PIN FUNCTIONS
Exposed Pad (DCB Package Only): Exposed pad may be
left open or connected to V
SS
.
GATE: Gate Drive Output. The GATE pin pulls high, enhanc-
ing the N-channel MOSFET when the load current creates
more than 30mV of voltage drop across the MOSFET.
When the load current is small, the gate is actively driven
to maintain 30mV across the MOSFET. If reverse current
flows,
a fast pull-down circuit connects the GATE to the
SOURCE pin within 0.3μs, turning off the MOSFET.
IN: Voltage Sense and Supply Voltage. IN is the anode of
the ideal diode. The voltage sensed at this pin is used to
control the MOSFET gate.
NC (MS Package Only): No Connection. Not internally
connected.
OUT: Drain Voltage Sense. OUT is the cathode of the ideal
diode
and the common output when multiple LTC4359s
are configured as an ideal diode-OR. It connects either di-
rectly or through a 2k resistor to the drain of the N-channel
MOSFET. The voltage sensed at this pin is used to control
the MOSFET gate.
SHDN: Shutdown Control Input. The LTC4359 can be
shut down to a low current mode by pulling the SHDN
pin below
0.6V. Pulling this pin above 2V or disconnect-
ing it allows an internal 2.6μA current source to turn the
part on. Maintain board leakage to less than 100nA for
proper operation. The SHDN pin can be pulled up to 100V
or down to –40V with respect to V
SS
without damage. If
the shutdown feature is not used, connect SHDN to IN.
SOURCE: Source Connection. SOURCE
is the return path
of the gate fast pull-down. Connect this pin as close as
possible to the source of the external N-channel MOSFET.
V
SS
: Supply Voltage Return and Device Ground.
TYPICAL PERFORMANCE CHARACTERISTICS
Gate Turn-Off Time
vs Initial Overdrive
Gate Turn-Off Time
vs Final Overdrive
Load Current
vs Forward Voltage Drop
V
INITIAL
(V)
0
t
PD
(ns)
150
200
1
4359 G10
100
50
0
0.50.25
0.75
V
IN
= 12V
∆V
SD
= V
INITIAL
–1V
V
FINAL
(V)
0
t
PD
(ns)
1500
–1
4359 G11
1000
500
0
–0.5–0.25
–0.75
V
IN
= 12V
∆V
SD
= 45mV V
FINAL
∆V
SD
(mV)
0
CURRENT (A)
10
100
4359 G12
8
2
4
6
0
5025
75
FDMS86101
FDB3632
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