LTC3414
TYPICAL PERFOR A CE CHARACTERISTICS
Load Step Transient Burst Mode
Operation
OUTPUT
VOLTAGE
100mV/DIV
V
RUN
OUTPUT
VOLTAGE
INDUCTOR
CURRENT
2A/DIV
V
IN
= 3.3V, V
OUT
= 2.5V
LOAD STEP = 250mA TO 4A
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
.
RT (Pin 2):
Oscillator Resistor Input. Connecting a resistor
to ground from this pin sets the switching frequency.
SYNC/MODE (Pin 3):
Mode Select and External Clock
Synchronization Input. To select Forced Continuous, tie to
SV
IN
. Connecting this pin to a voltage between 0V and 1V
selects Burst Mode operation with the burst clamp set to
the pin voltage.
RUN/SS (Pin 4):
Run Control and Soft-Start Input. Forcing
this pin below 0.5V shuts down the LTC3414. In shutdown
all functions are disabled. Less than 1µA of supply current
is consumed. A capacitor to ground from this pin sets the
ramp time to full output current.
SGND (Pin 5):Signal
Ground. All small signal components
and compensation components should connect to this
ground, which in turn connects to PGND at one point.
NC (Pin 6):
Open. No internal connection.
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.
NC (Pin 15):
Open. No internal connection.
SV
IN
(Pin 16):
Signal Input Supply. Decouple this pin to
SGND with a 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 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):
Should be connected to SGND and
soldered to the PCB.
U W
Start-Up Transient
INDUCTOR
CURRENT
2A/DIV
20µs/DIV
3414 G18
1ms/DIV
V
IN
= 3.3V, V
OUT
= 2.5V
LOAD = 4A
3414 G19
U
U
U
3414f
5
LINER [ LINEAR TECHNOLOGY ]
