Datasheet
5
LTC3413
3413fb
FU CTIO AL DIAGRA
U
U
W
–
+
–
+
–
+
–
+
–
+
9
16
10
PV
IN
3
I
TH
6
V
REF
1
8
SV
IN
SGND
4
V
FB
PGOOD
SV
IN
PV
IN
SLOPE
COMPENSATION
RECOVERY
SLOPE
COMPENSATION
PMOS CURRENT
COMPARATOR
NMOS CURRENT
COMPARATOR
OSCILLATOR
ERROR
AMPLIFIER
LOGIC
RUN
RUN/SSR
T
11
14
15
SW
SW
SW
SW
13
7
5
PGND
3413 BD
12
PGND
2
1.1V
REF
2
0.9V
REF
2
UU
U
PI FU CTIO S
SV
IN
(Pin 1): Signal Input Supply. Decouple this pin to
SGND with a capacitor. SV
IN
must be greater or equal to
PV
IN
, however, the difference between SV
IN
and PV
IN
must
be less than 0.5V.
PGOOD (Pin 2): Power Good Output. Open-drain logic
output that is pulled to ground when the output voltage is
not within ±10% of regulation point.
I
TH
(Pin 3): Error Amplifier Compensation Point. The
current comparator threshold increases with this control
voltage. Nominal voltage range for this pin is from 0.2V to
1.4V with 0.6V corresponding to the zero-sense voltage
(zero current).
V
FB
(Pin 4): Feedback Pin. Receives the feedback voltage
from the output.
R
T
(Pin 5): Oscillator Resistor Input. Connecting a resistor
to ground from this pin sets the switching frequency.
V
REF
(Pin 6): Reference Voltage Input. The positive input
of the internal error amplifier senses one-half of the
voltage at this pin through a resistor divider.
RUN/SS (Pin 7): Run Control and Soft-Start Input. Forcing
this pin below 0.5V shuts down the LTC3413. In shutdown
all functions are disabled drawing < 1μA of supply current.
A capacitor to ground from this pin sets the ramp time to
full output current.
SGND (Pin 8): Signal Ground. All small-signal compo-
nents and compensation components should connect to
this ground, which in turn connects to PGND at one point.
PV
IN
(Pins 9, 16): Power Input Supply. Decouple this pin
to PGND with a capacitor.
SW (Pins 10, 11, 14, 15): Switch Node Connection to
Inductor. This pin connects to the drains of the internal
main and synchronous power MOSFET switches.
PGND (Pins 12, 13): Power Ground. Connect this pin
closely to the (–) terminal of C
IN
and C
OUT
.
EXPOSED PAD (Pin 17): Should be connected to SGND.