LTC3405A-1.5 LINER [Linear Technology], LTC3405A-1.5 Datasheet - Page 5

• Manufacturer Part Number: LTC3405A-1.5
• Description: 1.5V, 1.8V, 1.5MHz, 300mA Synchronous Step-Down Regulators in ThinSOT
• Manufacturer: LINER [Linear Technology]

(From Figure 1a)
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.
100mV/DIV
200mA/DIV
200mA/DIV
PI FU CTIO S
TYPICAL PERFOR A CE CHARACTERISTICS
COUPLED
U
I
V
LOAD
OUT
AC
I
L
Load Step
V
V
I
PULSE SKIPPING MODE
LOAD =
IN
OUT
U
= 3.6V
= 1.8V
20mA TO 250mA
40 s/DIV
U
W
3405A1518 G20
U
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
resistive divider divides the output voltage down for com-
parison to the internal 1.2V reference voltage.
MODE (Pin 6): Mode Select Input. To select pulse skip-
ping mode, tie to V
Mode operation. Do not leave this pin floating.
IN
OUT
LTC3405A-1.5/LTC3405A-1.8
(Pin 4): Main Supply Pin. Must be closely decoupled
(Pin 5): Output Voltage Feedback Pin. An internal
3405A1518 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
sn3405a1518 3405a1518fs
3405A1518 G22
5