Datasheet

LTC3864
5
3864f
TYPICAL PERFORMANCE CHARACTERISTICS
Transient Response:
Burst Mode Operation
Dropout Behavior (100% Duty
Cycle) Low V
IN
Operation
Normal Soft Start-Up
Soft Start-Up into a Prebiased
Output Output Tracking
Pulse-Skipping Mode Operation
Waveforms
Burst Mode Operation
Waveforms
Transient Response:
Pulse-Skipping Mode Operation
T
A
= 25°C, unless otherwise noted.
V
IN
= 12V, V
OUT
= 5V
FIGURE 8 CIRCUIT
V
OUT
1V/DIV
SS
200mV/DIV
V
IN
5V/DIV
1ms/DIV
3864 G07
V
IN
= 12V, V
OUT
= 5V
I
LOAD
= 0.5mA
FIGURE 8 CIRCUIT
SS
200mV/DIV
V
OUT
1V/DIV
RUN
5V/DIV
1ms/DIV
3864 G08
V
OUT
PREBIASED
TO 2.9V
V
IN
= 12V, V
OUT
= 5V
I
LOAD
= 100mA
FIGURE 8 CIRCUIT
V
OUT
2V/DIV
SS
200mV/DIV
20ms/DIV
3864 G09
V
IN
TRANSIENT: 12V TO 4V
AND BACK TO 12V
V
OUT
= 5V, I
LOAD
= 100mA, FIGURE 8 CIRCUIT
GATE
10V/DIV
V
OUT
2V/DIV
V
IN
2V/DIV
50ms/DIV
3864 G05
V
OUT
= V
IN
IN DROPOUT
V
IN
= 0V TO 3.8V
THEN BACK TO 0V
I
LOAD
= 100mA
FIGURE 8 CIRCUIT
SW
5V/DIV
V
OUT
1V/DIV
V
IN
1V/DIV
20ms/DIV
3864 G06
V
OUT
PROGRAMMED TO 5V,
BUT STARTS UP IN DROPOUT
SINCE V
IN
< 5V
V
IN
= 12V
V
OUT
= 5V
I
LOAD
= 100mA
FIGURE 8 CIRCUIT
I
L
500mA/DIV
V
SW
10V/DIV
V
OUT
50mV/DIV
10µs/DIV
3864 G02
V
IN
= 12V
V
OUT
= 5V
I
LOAD
= 100mA
FIGURE 8 CIRCUIT
I
L
500mA/DIV
V
SW
10V/DIV
V
OUT
50mV/DIV
2µs/DIV
3864 G01
V
IN
= 12V
V
OUT
= 5V
TRANSIENT = 100mA TO 2A
FIGURE 8 CIRCUIT
I
L
2A/DIV
V
OUT
500mV/DIV
I
LOAD
2A/DIV
100µs/DIV
3864 G03
V
IN
= 12V
V
OUT
= 5V
TRANSIENT = 100mA TO 2A
FIGURE 8 CIRCUIT
I
L
2A/DIV
V
OUT
500mV/DIV
I
LOAD
2A/DIV
100µs/DIV
3864 G04