LTC3557-1 Linear Technology, LTC3557-1 Datasheet - Page 8

• Manufacturer Part Number: LTC3557-1
• Description: USB Power Manager
• Manufacturer: Linear Technology

www.DataSheet4U.com
LTC3557/LTC3557-1
TYPICAL PERFORMANCE CHARACTERISTICS
8
I
OUT2
50mV/DIV
50mV/DIV
100
2.5
2.4
2.3
2.2
2.1
2.0
1.9
1.8
1.7
1.6
1.5
90
80
70
60
50
40
30
20
10
300mA
0
0.01
V
V
–50
OUT2
OUT3
5mA
(AC)
(AC)
Oscillator Frequency vs
Temperature
Step-Down Switching Regulator 3
1.8V Output Effi ciency vs I
OPERATION
Burst Mode
–25
Step-Down Switching Regulator
Output Transient (MODE = 1)
V
V
I
OUT3
OUT2
OUT3
0.1
= 16mA
= 1.2V
= 1.8V
0
TEMPERATURE (°C)
V
1
I
OUT3
25
IN
= 2.9V
(mA)
50
50μs/DIV
10
PULSE SKIP
75
V
OUT3
V
V
V
V
V
100
IN3
IN3
OUT3
IN
IN
IN
100
= 3.8V
= 2.7V
= 5V
= 3.8V
= 5V
= 1.8V
35571 G16
35571 G13
1000
125
35571 G19
I
OUT2
50mV/DIV
50mV/DIV
100
400
350
300
250
200
150
100
20
10
90
80
70
60
50
40
30
300mA
0
0.01
V
V
2.5
OUT2
OUT3
5mA
Step-Down Switching Regulator 1
3.3V Output Effi ciency vs I
Step-Down Switching Regulator
Pulse Skip Supply Current vs V
(AC)
(AC)
OPERATION
Burst Mode
V
I
OUTX
OUTX
Step-Down Switching Regulator
Output Transient (MODE = 0)
V
V
I
OUT3
OUT2
OUT3
3.0
= 0mA
0.1
= 1.2V
= 100mA
= 1.2V
= 1.8V
3.5
1
I
OUT1
V
INX
(mA)
(V)
50μs/DIV
4.0
10
PULSE SKIP
V
OUT1
V
V
OUT1
100
IN1
IN1
4.5
= 3.8V
= 5V
= 3.3V
35571 G14
110°C
–45°C
75°C
25°C
35571 G17
T
INX
A
1000
= 25°C unless otherwise specifi ed
5.0
35571 G20
1200
1100
1000
100
600
900
800
700
500
400
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
20
10
0.1
90
80
70
60
50
40
30
0
0.01
0
–50
–50
Step-Down Switching Regulator 2
1.2V Output Effi ciency vs I
Step-Down Switching Regulator
Short-Circuit Current vs
Temperature
Step-Down Switching Regulator
Switch Impedance vs Temperature
V
INX
400mA
OPERATION
NMOS
Burst Mode
–25
–25
= 3.2V
0.1
0
TEMPERATURE (°C)
0
TEMPERATURE (°C)
600mA BUCK
400mA BUCK
400mA
1
I
PMOS
OUT2
25
25
PULSE SKIP
(mA)
600mA NMOS
50
50
10
75
V
600mA PMOS
75
OUT2
V
V
100
OUT2
IN2
IN2
100
100
= 3.8V
= 5V
= 1.2V
35571 G15
35571 G21
35571 G18
35571f
1000
125
125