Datasheet

LTC4360-1/LTC4360-2
9
436012fa
APPLICATIONS INFORMATION
L
IN
and R
IN
form an LC tank circuit with any capacitance
at IN. If the wall adaptor is powered up first, plugging
the wall adaptor output to IN does the equivalent of
applying a voltage step to this LC circuit. The resultant
voltage overshoot at IN can rise to twice the DC out-
Figure 4. 20V Hot-Plug into a 10µF Capacitor
+
LOAD
436012 F04a
MOBILE
DEVICE
WALL ADAPTOR
AC/DC
C
OUT
IN
L
IN
R
IN
CABLE
I
CABLE
V
IN
10V/DIV
I
CABLE
20A/DIV
5µs/DIV
436012 F04b
R
IN
= 150mΩ, L
IN
= 0.7µH
LOAD = 10Ω, C
OUT
= 10µF
put voltage of the wall adaptor as shown in Figure 4.
Figure 5 shows the 20V adaptor output applied to the
LTC4360. Due to the low capacitance at the IN pin, the
plug-in transient has been brought down to a manage-
able level.
Figure 5. 20V Hot-Plug into the LTC4360
+
LOAD
LTC4360
M1
Si1470DH
GND
GATE
436012 F04a
MOBILE
DEVICE
WALL ADAPTOR
AC/DC
C
OUT
IN OUT
L
IN
R
IN
CABLE
I
CABLE
IN OUT
V
IN
10V/DIV
V
OUT
1V/DIV
I
CABLE
20A/DIV
5µs/DIV
436012 F04b
R
IN
= 150mΩ, L
IN
= 0.7µH
LOAD = 10Ω, C
OUT
= 10µF