LTC3868 Linear Technology, LTC3868 Datasheet - Page 5

• Manufacturer Part Number: LTC3868
• Description: Low IQ Dual 2-Phase Synchronous Step-Down Controller
• Manufacturer: Linear Technology

Typical perForMance characTerisTics
100mV/DIV
COUPLED
2A/DIV
94
92
88
86
84
80
98
96
90
82
V
OUT
AC-
0
I
Efficiency vs Input Voltage
L
Load Step (Pulse-Skipping Mode)
V
FIGURE 12 CIRCUIT
OUT
5
= 3.3V
INPUT VOLTAGE (V)
100
90
80
70
60
50
40
30
20
10
10
0.0001
0
Efficiency and Power Loss
vs Output Current
FIGURE 12 CIRCUIT
V
V
20µs/DIV
IN
OUT
15
= 12V
0.001
FIGURE 12 CIRCUIT
V
I
= 3.3V
OUT
OUT
= 4A
OUTPUT CURRENT (A)
= 3.3V
20
0.01
25
3868 G03
3868 G06
0.1
28
100mV/DIV
CONTINUOUS
COUPLED
Burst Mode
OPERATION
PULSE-
SKIPPING
FCM
OPERATION
Burst Mode
2A/DIV
SKIPPING
1
FORCED
V
PULSE-
OUT
AC-
2A/DIV
MODE
MODE
I
3868 G01
L
Load Step (Burst Mode Operation)
V
FIGURE 12 CIRCUIT
OUT
10
Inductor Current at Light Load
V
I
FIGURE 12 CIRCUIT
LOAD
10000
1000
100
10
1
0.1
OUT
= 3.3V
= 3.3V
= 200µA
20µs/DIV
2µs/DIV
100
3868 G04
90
80
70
60
50
40
30
20
10
0.0001
0
3868 G07
Efficiency vs Output Current
V
IN
100mV/DIV
COUPLED
0.001
= 5V
2A/DIV
V
Soft Start-Up
FIGURE 12 CIRCUIT
OUT
AC-
OUTPUT CURRENT (A)
V
I
L
IN
0.01
Load Step
(Forced Continuous Mode)
V
FIGURE 12 CIRCUIT
= 12V
OUT
= 3.3V
V
FIGURE 12 CIRCUIT
0.1
OUT
www.DataSheet4U.com
20ms/DIV
= 3.3V
20µs/DIV
1
LTC3868
3868 G02
10
3868 G08
3868 G05
V
2V/DIV
V
2V/DIV
3868fb

OUT2
OUT1