LTC3613
PIN FUNCTIONS
RUN (Pin 26):
Digital Run Control Input. RUN self biases
high with an internal 1.3μA pull-up. Forcing RUN below
1.2V disables switching. Taking RUN below 0.75V shuts
down all bias and places the LTC3613 into micropower
shutdown mode of approximately 15μA.
EXTV
CC
(Pin 30):
External V
CC
Input. When EXTV
CC
exceeds
4.6V, an internal switch connects this pin to INTV
CC
and
shuts down the internal regulator so that the controller and
gate drive power is drawn from EXTV
CC
. EXTV
CC
should
not exceed V
IN
.
MODE/PLLIN (Pin 31):
External Clock Synchronization
Input and/or Forced Continuous Mode Input. When an
external clock is applied to this pin, the rising switching
cycle will be synchronized with the rising edge of the
external clock. Additionally, this pin determines operation
under light load conditions. When either a clock input is
detected or MODE/PLLIN is tied to INTV
CC
, forced continu-
ous mode operation is selected. Tying this pin to SGND
allows discontinuous pulse-skipping mode operation at
light loads.
SV
IN
(Pin 32):
Signal Input Supply. This pin powers the
internal control circuitry.
INTV
CC
(Pins 33, 34):
Internal 5.3V Regulator Output. The
driver and control circuits are powered from this voltage.
Decouple this pin to power ground with a minimum of
4.7μF ceramic capacitor (C
VCC
). The anode of the Schottky
diode, D
B
, connects to this pin.
PGND (Pins 36-44):
Power Ground Connection. Connect
this pin as close as practical to the (–) terminal of C
VCC
and the (–) terminal of C
IN
.
3613fa
9
LINEAR [ LINEAR INTEGRATED SYSTEMS ]
