Datasheet

LTC3415
17
3415fa
During ramp down of the output, if the TRACK pin is not
tied to V
IN
, then the LTC3415 will maintain normal opera-
tion even though the RUN pin is programmed low. Only
when the TRACK pin is below 0.18V will the RUN signal
be gated through internally and shut down the part. This
way, coincident tracking and ratiometric sequencing of the
two outputs are accomplished during both start-up and
shutdown. An output current load, however, needs to be
present during this time in order to discharge the output
because when TRACK is below 0.57V, forced continuous
operation is not allowed and inductor current, therefore,
is prevented from going negative.
For applications that do not require tracking or sequenc-
ing, simply tie the TRACK pin to SV
IN
to let RUN control
the turn on/off of the LTC3415. Connecting TRACK to
SV
IN
also enables the ~100μs of internal soft-start during
start-up.
OPERATION