LTC3642
(Refer to Block Diagram)
OPERATION
on the SS pin instead. The internal and external soft-start
functions are reset on start-up and after undervoltage or
overvoltage event on the input supply.
Peak Inductor Current Programming
The offset of the peak current comparator nominally
provides a peak inductor current of 115mA. This peak
inductor current can be adjusted by placing a resistor
In order to ensure a smooth start-up transition in any
application, the internal soft-start also ramps the peak
inductor current from 25mA during its 1ms ramp time to
the set peak current threshold. The external ramp on the
SS pin does not limit the peak inductor current during
from the I pin to ground. The 1ꢀA current sourced out
SET
of this pin through the resistor generates a voltage that is
translated into an offset in the peak current comparator,
which limits the peak inductor current.
start-up; however, placing a capacitor from the I
to ground does provide this capability.
pin
SET
3642f
9
Linear [ Linear ]
