Datasheet

LTC3855
6
3855f
Typical perForMance characTerisTics
Load Step
(Burst Mode Operation)
Load Step
(Forced Continuous Mode)
Load Step
(Pulse-Skipping Mode) Inductor Current at Light Load
Coincident TrackingPrebiased Output at 2V
V
IN
= 12V
V
OUT
= 1.8V
50µs/DIV
3855 G01
I
L
5A/DIV
V
OUT
100mV/DIV
AC-COUPLED
I
LOAD
5A/DIV
300mA TO 5A
V
IN
= 12V
V
OUT
= 1.8V
50µs/DIV
3855 G02
I
L
5A/DIV
V
OUT
100mV/DIV
AC-COUPLED
I
LOAD
5A/DIV
300mA TO 5A
V
IN
= 12V
V
OUT
= 1.8V
50µs/DIV
3855 G03
I
L
5A/DIV
V
OUT
100mV/DIV
AC-COUPLED
I
LOAD
5A/DIV
300mA TO 5A
V
IN
= 12V
V
OUT
= 1.8V
I
LOAD
= 400mA
1µs/DIV
3855 G04
FORCED
CONTINUOUS MODE
5A/DIV
Burst Mode
OPERATION
5A/DIV
PULSE-SKIPPING
MODE
5A/DIV
V
IN
= 12V
V
OUT
= 3.3V
2ms/DIV
3855 G05
TK/SS
500mV/DIV
V
FB
500mV/DIV
V
OUT
2V/DIV
5ms/DIV
3855 G06
RUN
2V/DIV
V
OUT1
V
OUT2
1V/DIV
V
OUT1
V
OUT2
V
OUT1
= 1.8V, 1.5Ω LOAD
V
OUT2
= 1.2V, 1Ω LOAD