SC2440AEVB datasheet(11/28 Pages) SEMTECH

11 / 28 page

General Description (Continued)

SC2440A

causes the converter output voltage to fall below 72% of its

set point, then the converter will be shut off immediately,

without waiting for V

COMP to rise to its clamp level. The con-

verter restarts after timing out.

The output power good comparator indicates that the

channel output voltage has risen to within 0% of its set

value. Each regulator of the SC2440A has its own output

good comparator. The open collector output of the voltage

ready comparator will be actively pulled low if the corre-

sponding feedback voltage is below 0.9V.

enabling SS discharge. The net soft-start capacitor discharg-

ing current is I

D - IC ≈ .2µA. The switching regulator remains

off until the soft-start capacitor is discharged below V. At

this moment, the SS discharge latch is reset. The soft-start

capacitor is recharged and the converter again undergoes

soft-start, delaying converter restart until the hiccup cycle

completes, reducing power dissipation in overload. The

regulator will go through soft-start, overload shutdown

and restart until it is no longer overloaded. Comparator

4 resets latch X3 during initial start-up or before recover-

ing from overload shutdown. Comparator X

5 monitors the

output voltage after hiccup is armed. If excessive overload

SC2440AEVB Datasheet(PDF) 11 Page - Semtech Corporation