ltc3405a-1.375 Linear Technology Corporation, ltc3405a-1.375 Datasheet - Page 5

• Manufacturer Part Number: ltc3405a-1.375
• Description: 1.375v, 1.5mhz, 300ma Synchronous Step-down Regulators In Thinsot
• Manufacturer: Linear Technology Corporation

(From Figure 1a)
100mV/DIV
200mA/DIV
200mA/DIV
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 <1µA 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.
PI FU CTIO S
TYPICAL PERFOR A CE CHARACTERISTICS
COUPLED
U
I
V
LOAD
OUT
AC
I
L
Load Step
V
I
PULSE SKIPPING MODE
LOAD =
IN
= 3.6V
U
20mA TO 250mA
20µs/DIV
U
W
3405A1375 G17
U
100mV/DIV
200mA/DIV
200mA/DIV
COUPLED
I
V
LOAD
OUT
AC
I
L
Load Step
V
I
Burst Mode OPERATION
LOAD =
IN
= 3.6V
20mA TO 250mA
20µs/DIV
V
to GND, Pin 2, with a 2.2µF or greater ceramic capacitor.
V
resistive divider divides the output voltage down for com-
parison to the internal 0.9V 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
(Pin 4): Main Supply Pin. Must be closely decoupled
(Pin 5): Output Voltage Feedback Pin. An internal
3405A1375 G18
T
A
= 25°C unless otherwise noted.
100mV/DIV
200mA/DIV
200mA/DIV
COUPLED
IN
. Grounding this pin selects Burst
I
V
LOAD
OUT
AC
I
L
Load Step
V
I
Burst Mode OPERATION
LTC3405A-1.375
LOAD =
IN
= 3.6V
0mA TO 250mA
20µs/DIV
3405a1375f
3405A1375 G19
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