LTC3405 Linear Technology, LTC3405 Datasheet - Page 5

• Manufacturer Part Number: LTC3405
• Description: Dual DC/DC Converter with USB Power Manager and Li-Ion Battery Charger
• Manufacturer: Linear Technology

www.DataSheet4U.com
(From Figure 1a Except for the Resistive Divider Resistor Values)
100mV/DIV
200mA/DIV
200mA/DIV
TYPICAL PERFOR A CE CHARACTERISTICS
PI FU CTIO S
RUN (Pin 1): Run Control Input. Forcing this pin above
1.5V enables the part. Forcing this pin below 0.3V shuts
down the device. In shutdown, all functions are disabled
drawing <1 A supply current. Do not leave RUN floating.
GND (Pin 2): Ground Pin.
SW (Pin 3): Switch Node Connection to Inductor. This pin
connects to the drains of the internal main and synchro-
nous power MOSFET switches.
COUPLED
U
I
V
LOAD
OUT
AC
I
L
Load Step
V
V
I
PULSE SKIPPING MODE
LOAD =
IN
OUT
= 3.6V
U
= 1.8V
20mA TO 250mA
40 s/DIV
U
W
U
3405 G20
100mV/DIV
200mA/DIV
200mA/DIV
COUPLED
I
V
LOAD
OUT
AC
I
L
Load Step
V
V
I
Burst Mode OPERATION
LOAD =
IN
OUT
= 3.6V
= 1.8V
20mA TO 250mA
40 s/DIV
V
to GND, Pin 2, with a 2.2 F or greater ceramic capacitor.
V
from an external resistive divider across the output.
MODE (Pin 6): Mode Select Input. To select pulse skip-
ping mode, tie to V
Mode operation. Do not leave this pin floating.
IN
FB
(Pin 4): Main Supply Pin. Must be closely decoupled
(Pin 5): Feedback Pin. Receives the feedback voltage
3405 G21
100mV/DIV
200mA/DIV
200mA/DIV
COUPLED
IN
. Grounding this pin selects Burst
I
V
LOAD
OUT
AC
I
L
Load Step
V
V
I
Burst Mode OPERATION
LOAD =
IN
OUT
= 3.6V
= 1.8V
0mA TO 250mA
40 s/DIV
LTC3405
sn3405 3405fs
3405 G22
5