LTC4360-1/LTC4360-2

9

436012f

APPLICATIONS INFORMATION

Figure 6. 50V Hot-Plug into the LTC4360

Figure 7. Input Transient After Overvoltage

20V/DIV

1V/DIV

5A/DIV

5μs/DIV

436012 F05

FDC5612

5V/DIV

20V/DIV

5A/DIV

2μs/DIV

436012 F06

FIGURE 5 CIRCUIT

As the IN pin can withstand up to 80V, a high voltage N-

channel MOSFET can be used to protect the system against

rugged abuse from high transient or DC voltages up to the

into the LTC4360 controlling a 60V rated MOSFET.

Input transients also occur when the current through the

cable inductance changes abruptly. This can happen when

the LTC4360 turns off the N-channel MOSFET rapidly in an

overvoltage event. Figure 7 shows the effects of a voltage

Figure 5. 20V Hot-Plug into the LTC4360

+

LOAD

LTC4360

M1

Si1470DH

GND

GATE

436012 F04a

MOBILE

DEVICE

WALL ADAPTOR

AC/DC

IN

OUT

CABLE

IN

OUT

10V/DIV

1V/DIV

20A/DIV

5μs/DIV

436012 F04b

This is well below the 85V absolute maximum voltage

rating of the LTC4360. The single, nonrepetitive, pulse of

by the formula:

the Si1470DH. So in most instances, the LTC4360 can

ride through such transients without a bypass capacitor,

transient voltage suppressor or other external components

at IN.