LTC3576 Datasheet, PDF (11/48 Pages) Linear Technology – Switching Power Manager with USB On-the-Go + Triple Step-Down DC/DCs

LTC3576/LTC3576-1
TYPICAL PERFORMANCE CHARACTERISTICS T_A = 25°C unless otherwise specified.
3.3V LDO Output Voltage vs
Load Current, V_BUS = 0V
3.4
BAT = 3.9V, 4.2V BAT = 3.4V
BAT = 3.5V
3.2
BAT = 3.6V
3.3V LDO Step Response
(5mA to 15mA)
I_LDO3V3
5mA/DIV
0mA
3.0
2.8 ^{BAT = 3V}
BAT = 3.1V
BAT = 3.2V
BAT = 3.3V
2.6
0
5
10
15
20
LOAD CURRENT (mA)
V_LDO3V3
20mV/DIV
AC COUPLED
BAT = 3.8V
25
3576 G37
20μs/DIV
3576 G38
Switching Regulator Soft-Start
Waveform
Switching Regulator Current Limit
vs Temperature
2.0
REGULATOR 3
1.5
50μs/DIV
3576 G40
Switching Regulator Low Power
Quiescent Currents vs Temperature
100
90
PULSE-SKIP MODE
80
70
60
50
40
30
Burst Mode OPERATION
20
10
LDO MODE
0
–40 –15 10
35
60
85
TEMPERATURE (°C)
3576 G43
1.0
REGULATORS 1, 2
0.5
V_IN1,2,3 = 3.8V
0
–40 –15 10
35
60
85
TEMPERATURE (°C)
3576 G41
Switching Regulators 1, 2
Pulse-Skip Mode Efficiency
100
V_IN3 = 3.8V
90
V_OUT1,2 = 2.5V
80
V_OUT1,2 = 1.2V
70
V_OUT1,2 = 1.8V
60
50
40
30
20
10
0
0.1
1
10
100
1000
LOAD CURRENT (mA)
3576 G44
Battery Drain Current vs
Battery Voltage
35
I_VOUT = 0mA
30
V_BUS = 0V
25
20
15
10
V_BUS = 5V
5
(SUSPEND MODE)
0
2.7 3.0 3.3 3.6 3.9 4.2
BATTERY VOLTAGE (V)
3576 G39
R_DS(ON) for Switching Regulator
Power Switches vs Temperature
1.0
REGULATORS 1, 2
0.8
NMOS SWITCH
0.6
PMOS SWITCH
0.4
REGULATOR 3
0.2
NMOS SWITCH
PMOS SWITCH
0
–40 –15 10
35
60
85
TEMPERATURE (°C)
3576 G42
Switching Regulators 1, 2
Burst Mode Efficiency
100
V_IN3 = 3.8V V_OUT1,2 = 2.5V
90
80
V_OUT1,2 = 1.2V
70
V_OUT1,2 = 1.8V
60
50
40
30
20
10
0
0.1
1
10
100
LOAD CURRENT (mA)
1000
3576 G45
3576f
11