9

LTC3427

3427fa

The LTC3427 will maintain voltage regulation when the

input voltage is above the output voltage. This is achieved

by terminating the switching of the synchronous P-chan-

will ensure the volt • seconds across the inductor reverse

during the time current is flowing to the output. Since this

mode will dissipate more power in the LTC3427, the

maximum output current is limited in order to maintain an

acceptable junction temperature and is given by:

I

T

VV

OUT MAX

A

IN

OUT

()

–

•.

–

=

+

()

⎡⎣

⎤⎦

125

85

1 5

maximum output current is 145mA.

Short-Circuit Protection

The LTC3427 output disconnect feature allows output

short circuit while maintaining a maximum internally set

current limit. However, the LTC3427 also incorporates

internal features such as current limit foldback and ther-

mal shutdown for protection from an excessive overload

or short circuit. During a prolonged short circuit the

current limit folds back to a typical value of approximately

mately 1V, at which time the nominally internally set

current limit is restored.

APPLICATIO S I FOR ATIO