LTC3769_15 Datasheet, PDF (5/32 Pages) Linear Technology – 60V Low IQ Synchronous Boost Controller

LTC3769
Typical Performance Characteristics T_A = 25°C unless otherwise noted.
Efficiency and Power Loss
vs Output Current
100
10
90
80
1
70
60
0.1
50
40
30
20
10
0
0.01
V_IN = 12V
V_OUT = 24V
0.01
FIGURE 8 CIRCUIT
FCM EFFICIENCY
FCM LOSS
0.001
PULSE-SKIPPING EFFICIENCY
PULSE-SKIPPING LOSS
0.0001
0.1
1
10
OUTPUT CURRENT (A)
3769 G01
Efficiency and Power Loss
vs Output Current
100
10
90
EFFICIENCY
1
80
70
POWER
0.1
LOSS
60
50
40
0.0001
0.001 0.01
0.01
V_IN = 12V
V_OUT = 24V
FIGURE 8 CIRCUIT
0.001
0.1
1
10
OUTPUT CURRENT (A)
3769 G02
Efficiency vs Input Voltage
100
I_LOAD = 2A
99 ^{FIGURE 8 CIRCUIT}
98
V_OUT = 12V
97
V_OUT = 24V
96
Load Step
Forced Continuous Mode
LOAD STEP
2A/DIV
INDUCTOR
CURRENT
5A/DIV
V_OUT
500mV/DIV
95
94
93
0
5
10
15
20
25
INPUT VOLTAGE (V)
3769 G03
V_IN = 12V
200µs/DIV
V_OUT = 24V
LOAD STEP FROM 200mA TO 2.5A
FIGURE 8 CIRCUIT
Load Step
Burst Mode Operation
LOAD STEP
2A/DIV
INDUCTOR
CURRENT
5A/DIV
V_OUT
500mV/DIV
3769 G04
V_IN = 12V
200µs/DIV
V_OUT = 24V
LOAD STEP FROM 200mA TO 2.5A
FIGURE 8 CIRCUIT
3769 G05
Load Step
Pulse-Skipping Mode
LOAD STEP
2A/DIV
INDUCTOR
CURRENT
5A/DIV
V_OUT
500mV/DIV
V_IN = 12V
200µs/DIV
V_OUT = 24V
LOAD STEP FROM 200mA TO 2.5A
FIGURE 8 CIRCUIT
Inductor Currents at Light Load
Soft Start-Up
FORCED
CONTINUOUS
MODE
Burst Mode
OPERATION
5A/DIV
PULSE-
SKIPPING MODE
3769 G06
V_IN = 12V
5µs/DIV
V_OUT = 24V
I_LOAD = 200µA
FIGURE 8 CIRCUIT
V_OUT
5V/DIV
3769 G07
V_RUN
5V/DIV
0V
V_IN = 12V
20ms/DIV
V_OUT = 24V
FIGURE 8 CIRCUIT
3769 G08
3769f
For more information www.linear.com/LTC3769
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