LTC3412A Datasheet, PDF (4/20 Pages) Linear Technology – 3A, 4MHz, Monolithic Synchronous Step-Down Regulator

LTC3412A
TYPICAL PERFOR A CE CHARACTERISTICS
Efficiency vs Load Current
100
90 _{Burst Mode}
80 ^OPERATION
70
FORCED
60
CONTINUOUS
50
40
30
20
10
0
0.01
V_IN = 3.3V
V_OUT = 2.5V
FIGURE 4 CIRCUIT
0.1
1
LOAD CURRENT (A)
10
3412A GO1
Efficiency vs Load Current, Burst
Mode Operation
100
95
V_IN = 3.3V
90
85
V_IN = 5V
80
75
70
65
60
55
50
0.01
V_OUT = 2.5V
FIGURE 4 CIRCUIT
0.1
1
LOAD CURRENT (A)
10
3412A GO2
Efficiency vs Input Voltage
94
FIGURE 4 CIRCUIT
92
1A
90
0.1A
88
86
84
3A
82
80
2.5
3.0
3.5
4.0 4.5
5.0
INPUT VOLTAGE (V)
3412A GO4
Efficiency vs Frequency
96
95
1μH
FIGURE 4 CIRCUIT
V_IN = 3.3V
94
0.22μH
93
0.47μH
92
91
90
89
88
87
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
FREQUENCY (MHz)
3412A GO5
Burst Mode Operation
Output Voltage Ripple
Efficiency vs Load Current,
Forced Continuous Operation
100
90
V_IN = 3.3V
80
70
V_IN = 5V
60
50
40
30
20
10
0
0.01
V_OUT = 2.5V
FIGURE 4 CIRCUIT
0.1
1
LOAD CURRENT (A)
10
3412A GO3
Load Regulation
0
–0.1
FIGURE 4 CIRCUIT
V_IN = 3.3V
–0.2
–0.3
–0.4
–0.5
–0.6
0
0.5 1.0 1.5 2.0 2.5 3.0
LOAD CURRENT (A)
3412A GO6
Load Step Transient Burst Mode
Operation
V_OUT
20mV/DIV
INDUCTOR
CURRENT
1A/DIV
FIGURE 4 CIRCUIT 5μs/DIV
4
BURST
MODE
20mV/DIV
PULSE
SKIPPING
20mV/DIV
FORCED
CONTINUOUS
20mV/DIV
3412A GO7
V_IN = 3.3V
5μs/DIV
V_OUT = 2.5V
FIGURE 4 CIRCUIT
V_OUT
100mV/DIV
INDUCTOR
CURRENT
2A/DIV
3412A GO8
V_IN = 3.3V
V_OUT = 2.5V
F = 1MHz
40μs/DIV
LOAD STEP = 50mA TO 2A
FIGURE 4 CIRCUIT
3412A GO9
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