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LTC4001-1_15 Datasheet, PDF (4/20 Pages) Linear Technology – 2A Synchronous Buck Li-Ion Charger
LTC4001-1
TYPICAL PERFORMANCE CHARACTERISTICS (TA = 25°C unless otherwise noted)
Oscillator Frequency vs VIN
1.00
VBAT = 3.2V
0.75 VSS = 1V
0.50
0.25
0
–0.25
–0.50
–0.75
–1.00
3 3.5 4 4.5 5 5.5 6
VIN (V)
40011 G01
Dissipation of Figure 8 Circuit
vs VIN
1.4
VBAT = 4V
IBAT = 2A
1.2
1.0
0.8
IBAT = 1.5A
0.6
IBAT = 1A
0.4
IBAT = 500mA
0.2
0
4.25 4.5 4.75
5
VIN (V)
5.25 5.5
40011 G04
Oscillator Frequency
vs Temperature
0.8
VIN = 5V
VBAT = 3.2V
0.6 VSS = 1V
0.4
0.2
0
–0.2
–50 –30 –10 10 30 50 70 90 110 130 150
TEMPERATURE (°C)
40011 G02
PROG Pin Characteristic
(VPROG vs IPROG)
1.2
VIN = 5V
1.0
VBAT = 3.2V
VBAT = 4V
0.8
VBAT = 3.5V
VBAT = 3.7V
0.6
0.4
0.2
0
0
5
10
15
20
IPROG (mA)
40011 G05
Dissipation of Figure 8 Circuit
vs IBAT
1.25
VIN = 5V
VBAT = 4V
1.00
0.75
0.50
0.25
0
500
1000
1500
2000
IBAT (mA)
40011 G03
Output Charging Characteristic
Showing Constant Current and
Constant Voltage Operation
2.0
1.5
1.0
0.5
0
0 0.5 1 1.5 2 2.5 3 3.5 4
VBAT (V)
40011 G06
Trickle Charge Current vs VBAT
55
VFLOAT and Recharge Battery
Threshold Voltage vs Temperature
4.2
VIN = 5.5V
50
VIN = 5V
VIN = 4V
VIN = 4.5V
45
VFLOAT
4.1
VRECHARGE
(VBAT FALLING)
4.0
4
40
0 0.5 1 1.5 2 2.5 3
VBAT (V)
40011 G07
3.9
–50 –30 –10 10 30 50 70 90 110 130 150
TEMPERATURE (°C)
40011 G08
40011fa