LTC3550 Datasheet, PDF (5/24 Pages) Linear Technology – Dual Input USB/AC Adapter Li-Ion Battery Charger with 600mA Buck Converter

LTC3550
TYPICAL PERFOR A CE CHARACTERISTICS T_A = 25°C, unless otherwise noted.
Regulated Charger Output (Float)
Voltage vs Charge Current
4.26
V_DCIN = V_USBIN = 5V
4.24
4.22
4.20
4.18
4.16
R_IDC = R_IUSB = 2k RIDC = 1.25k
4.14
4.12
4.10
0
100 200 300 400 500 600 700 800
CHARGE CURRENT (mA)
3550 G01
IUSB Pin Voltage vs Temperature
(Constant-Current Mode)
1.008
HPWR = 5V
1.006
1.004
1.002
1.000
0.998
V_USBIN = 8V
V_USBIN = 4.3V
0.996
0.994
0.992
–50 –25 0 25 50 75 100
TEMPERATURE (°C)
3550 G04
Charge Current
vs IUSB Pin Voltage
900
V_USBIN = 5V
800
700
R_IUSB = 1.25k
600
R_IUSB = 2k
500
400
300
200
R_IUSB = 10k
100
0
0 0.2 0.4 0.6 0.8 1.0 1.2
V_IUSB (V)
3550 G06
Regulated Charger Output (Float)
Voltage vs Temperature
4.220
4.215
V_DCIN = V_USBIN = 5V
4.210
4.205
4.200
4.195
4.190
4.185
4.180
–50
–25 0 25 50
TEMPERATURE (°C)
75 100
3550 G02
IUSB Pin Voltage vs Temperature
(Constant-Current Mode)
0.208
HPWR = 0V
0.206
0.204
0.202
0.200
0.198
V_USBIN = 8V
V_USBIN = 4.3V
0.196
0.194
0.192
–50 –25 0
25 50 75 100
TEMPERATURE (°C)
3550 G43
⎯P⎯W⎯R Pin I-V Curve
35
V_DCIN = V_USBIN = 5V
30
25
20
T_A = – 40°C
T_A = 25°C
T_A = 90°C
15
10
5
0
01
2 34 5
V_PWR (V)
67
3550 G07
IDC Pin Voltage vs Temperature
(Constant-Current Mode)
1.008
1.006
1.004
1.002
1.000
0.998
V_DCIN = 8V
V_DCIN = 4.3V
0.996
0.994
0.992
–50
–25 0 25 50
TEMPERATURE (°C)
75 100
3550 G03
Charge Current vs IDC Pin Voltage
900
V_DCIN = 5V
800
700
R_IDC = 1.25k
600
R_IDC = 2k
500
400
300
200
R_IDC = 10k
100
0
0 0.2 0.4 0.6 0.8 1.0 1.2
V_IDC (V)
3550 G05
⎯C⎯H⎯R⎯G Pin I-V Curve
35
V_DCIN = V_USBIN = 5V
30
25
20
T_A = – 40°C
T_A = 25°C
T_A = 90°C
15
10
5
0
01
2 34 5
V_CHRG (V)
67
3550 G08
3550fa
5