LTC3553-2_15 Datasheet, PDF (9/36 Pages) Linear Technology – Micropower USB Power Manager with Li-Ion Charger, Always-On LDO and Buck Regulator

LTC3553-2
TYPICAL PERFORMANCE CHARACTERISTICS T_A = 25°C, unless otherwise specified.
Buck Regulator 3.3V Output
Efficiency vs Load
100
STBY = L
90
80
70
60
50
40
30
20
10
0
0.01
3.8V
5V
0.1
1
10 100
BUCK LOAD (mA)
1000
35532 G19
Buck Switching Regulator 2.5V
Output Efficiency vs Load
100
STBY = L
90
80
70
60
50
40
30
20
10
0
0.01
3.8V
5V
0.1
1
10 100
BUCK LOAD (mA)
1000
35532 G20
Buck Switching Regulator 1.8V
Output Efficiency vs Load
100
STBY = L
90
80
70
60
50
40
30
20
10
0
0.01
3.8V
5V
0.1
1
10 100
BUCK LOAD (mA)
1000
35532 G21
Buck Regulator 1.2V Output
Efficiency vs I_LOAD
100
STBY = L
90
80
70
60
50
40
30
20
10
0
0.01
3.8V
5V
0.1
1
10 100
BUCK LOAD (mA)
1000
35532 G22
Buck Regulator Burst Mode^®
Operation BVIN Supply Current
35
NO LOAD
30 ^{STBY = L}
–45°C
25°C
90°C
25
20
15
10
5
0
2.5 3 3.5 4 4.5 5 5.5
BVIN SUPPLY VOLTAGE (V)
35532 G23
Buck Regulator Standby Mode
BVIN Supply Current
3.0
NO LOAD
–45°C
STBY = H
25°C
2.5
90°C
2.0
1.5
1.0
0.5
0
2.5 3 3.5 4 4.5 5 5.5
BVIN SUPPLY VOLTAGE (V)
35532 G24
Buck Regulator Short-Circuit
Current vs Temperature
500
STBY = L
480
Buck Regulator Output Transient
(STBY = High)
V_OUT
50mV/DIV
(AC)
Buck Regulator Output Transient
(STBY = Low)
V_OUT
50mV/DIV
(AC)
BUCK (1.2V)
460
10mV/DIV
(AC)
440
5mA
I_BUCK
100μA
420
400
–75 –50 –25 0 25 50 75 100 125 150
TEMPERATURE (°C)
V_BUS = 0V
V_BAT = 3.8V
STBY = HIGH
50μs/DIV
BUCK (1.2V)
50mV/DIV
(AC)
100mA
I_BUCK
1mA
35532 G26
V_BUS = 0V
V_BAT = 3.8V
STBY = LOW
100μs/DIV
35532 G27
35532 G25
35532f
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