LTC3577_15 Datasheet, PDF (13/54 Pages) Linear Technology – Highly Integrated 6-Channel Portable PMIC

LTC3577/LTC3577-1
TYPICAL PERFORMANCE CHARACTERISTICS T_A = 25°C unless otherwise specified
Step-Down Switching Regulator 3
1.2V Output Efficiency vs I_OUT3
100
90
Burst Mode
80 OPERATION
70
60
PULSE-SKIPPING MODE
50
Step-Down Switching Regulator 3
2.5V Output Efficiency vs I_OUT3
100
90
Burst Mode
OPERATION
80
70
PULSE-SKIPPING MODE
60
50
Step-Down Switching Regulator
Short-Circuit Current vs Temperature
1500
1400
1300
1200
800mA BUCK
1100
1000
40
40
900
500mA BUCK
30
30
800
20
V_OUT3 = 1.2V
10
V_IN3 = 3.8V
V_IN3 = 5V
0
0.01 0.1
1
10 100 1000
I_OUT (mA)
3577 G22
Step-Down Switching Regulator
Output Transient (Burst Mode
Operation)
20
V_OUT3 = 2.5V
10
V_IN3 = 3.8V
V_IN3 = 5V
0
0.01 0.1
1
10 100 1000
I_OUT (mA)
3577 G23
Step-Down Switching Regulator
Output Transient (Pulse-Skipping
Mode)
V_OUT1
50mV/DIV
(AC)
V_OUT2
50mV/DIV
(AC)
V_OUT3
100mV/DIV
(AC)
V_OUT1
50mV/DIV
(AC)
V_OUT2
50mV/DIV
(AC)
V_OUT3
100mV/DIV
(AC)
500mA
I_{OUT3 5mA}
V_OUT1 = 3.3V
50μs/DIV
I_OUT1 = 10mA
V_OUT2 = 1.8V
I_OUT2 = 20mA
V_OUT3 = 1.2V
V_OUT = V_BAT = 3.8V
3577 G25
500mA
I_{OUT3 5mA}
V_OUT1 = 3.3V
50μs/DIV
I_OUT1 = 30mA
V_OUT2 = 1.8V
I_OUT2 = 20mA
V_OUT3 = 1.2V
V_OUT = V_BAT = 3.8V
3577 G26
800mA Step-Down Switching
Regulator Feedback Voltage
vs Output Current
0.85
500mA Step-Down Switching
Regulator Feedback Voltage
vs Output Current
0.85
700
600
500
–50 –25
V_INx = 3.8V
V_INx = 5V
0 25 50 75 100 125
TEMPERATURE (°C)
3577 G24
Step-Down Switching Regulator
Switch Impedance vs Temperature
0.9
V_INX = 3.2V
0.8
0.7
500mA
0.6 _NMOS
500mA
PMOS
0.5
0.4
800mA PMOS
0.3
800mA NMOS
0.2
0.1
0
–50 –25
0 25 50 75
TEMPERATURE (°C)
100 125
3577 G27
LDO Load Step
0.84
0.83
0.82
Burst Mode
OPERATION
0.81
0.80
PULSE-SKIPPING MODE
0.79
0.84
0.83
0.82
Burst Mode
OPERATION
0.81
0.80
0.79
PULSE-SKIPPING MODE
LDO1
50mV/DIV
(AC)
LDO2
20mV/DIV
(AC)
0.78
0.77
0.76
0.75
0.1
1
10
100
OUTPUT CURRENT (mA)
3.8V
5V
1000
3577 G28
0.78
0.77
0.76
0.75
0.1
1
10
100
OUTPUT CURRENT (mA)
100mA
I_{OUT1 5mA}
3.8V
5V
1000
LDO1 = 1.2V
20μs/DIV
LDO2 = 2.5V
I_LDO2 = 40mA
V_OUT = V_BAT = 3.8V
3577 G29
3577 G30
3577fa
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