LTC3416
5
3416fa
UU
U
PI FU CTIO S
PGND (Pins 1, 10, 11, 20): Power Ground. Connect this
pin closely to the (–) terminal of C
IN
and C
OUT
.
R
T
(Pin 2): Oscillator Resistor Input. Connecting a resistor
to ground from this pin sets the switching frequency.
TRACK (Pin 3): Tracking Voltage Input. Applying a voltage
that is less than 0.8V to this pin enables tracking. During
tracking, the V
FB
pin will regulate to the voltage on this pin.
Do not float this pin.
RUN/SS (Pin 4): Run Control and Soft-Start Input. Forcing
this pin below 0.5V shuts down the LTC3416. 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 5): Signal Ground. All small-signal compo-
nents and compensation components should connect to
this ground, which in turn connects to PGND at one point.
NC (Pins 6, 15): No Connect.
PV
IN
(Pins 7, 14): Power Input Supply. Decouple this pin
to PGND with a capacitor.
SW (Pins 8, 9, 12, 13): Switch Node Connection to
Inductor. This pin connects to the drains of the internal
main and synchronous power MOSFET switches.
SV
IN
(Pin 16): Signal Input Supply. Decouple this pin to
the SGND capacitor.
PGOOD (Pin 17): Power Good Output. Open-drain logic
output that is pulled to ground when the output voltage is
not within ±7.5% of the regulation point.
I
TH
(Pin 18): 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 0.4V corresponding to the zero-sense voltage
(zero current).
V
FB
(Pin 19): Feedback Pin. Receives the feedback voltage
from a resistive divider connected across the output.
Exposed Pad (Pin 21): Ground. Connect to SGND.
