Datasheet

LTC3553
8
3553fb
TYPICAL PERFORMANCE CHARACTERISTICS
Battery Charge Current
vs Battery Voltage
Forward Voltage
vs Ideal Diode Current V
BUS
Connect Waveform V
BUS
Disconnect Waveform
V
FLOAT
Load Regulation
Battery Regulation (Float)
Voltage vs Temperature
T
A
= 25°C, unless otherwise specifi ed.
I
BAT
(mA)
050
4.192
V
FLOAT
(V)
4.196
4.198
4.204
4.202
4.200
200150 250 350 450
400
3553 G10
4.194
100 300
V
BUS
= 5V
HPWR = H
TEMPERATURE (°C)
–75 –25–50
4.150
V
FLOAT
(V)
4.200
4.225
4.250
50
100
125
3553 G11
4.175
25075
V
BUS
= 5V
I
BAT
= 2mA
I
BAT
(mA)
0 400200
0
V
FWD
(mV)
100
150
250
300
200
1000 1200
3553 G13
50
800600
V
BUS
= 5V
V
BUS
= 0V
V
BAT
= 3.8V
I
LDO
= 100mA
I
BUCK
= 100mA
HPWR = HIGH
SUSP = LOW
STBY = LOW
20µs/DIV
5V
3.8V
BUCK (1.2V)
V
BUS
V
OUT
0V
3553 G14
LDO (3.3V)
V
BAT
= 3.8V
I
LDO
= 100mA
I
BUCK
= 100mA
HPWR = HIGH
SUSP = LOW
STBY = LOW
3553 G15
100µs/DIV
5V
3.8V
V
BUS
V
BUS
BUCK (1.2V)
V
OUT
V
OUT
0V
LDO (3.3V)
Oscillator Frequency
vs Temperature
Switching from Suspend Mode to
500mA Mode
V
BAT
= 3.75V
I
OUT
= 50mA
R
PROG
= 2k
HPWR
=
HIGH
3553 G17
1ms/DIV
5V
5V
SUSP
V
OUT
0
0
0A
0A
I
BUS
0.5A/DIV
I
BAT
0.5A/DIV
Switching from 100mA Mode to
500mA Mode
V
BAT
= 3.75V
I
OUT
= 50mA
R
PROG
= 2k
SUSP = LOW
3553 G16
1ms/DIV
5V
HPWR
0
0A
0A
I
BUS
0.5A/DIV
I
BAT
0.5A/DIV
V
BAT
(V)
2 2.4 3.6 43.22.8
0
I
BAT
(mA)
200
300
500
400
3553 G12
100
4.4
V
BUS
= 5V
HPWR = H
R
PROG
= 1.87k
TEMPERATURE (°C)
–50 –30 –10 30 50 70 90 13011010
0.95
OSCILLATOR FREQUENCY (MHz)
1.05
1.10
1.20
1.30
1.25
1.15
3553 G18
1.00
2.7V
3.8V
5.5V