LTC1559-3.3/LTC1559-5
U W
TYPICAL PERFORMANCE CHARACTERISTICS
Boost Converter Switching
Frequency
Output Power vs Battery Voltage
Backup Time vs Battery Capacity
140
120
100
80
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
125
100
75
50
25
0
I
= 330mA
= 200µF
V
BAT
P
OUT
= 1.2V
= 100mW
LTC1559-3.3
PK
L
C
V
PK
= 1.2V
BAT
I
= 330mA
60
40
20
0
4
6
8
2
1.0
1.1
1.2
1.3
1.4
50
125
250
375
500
10
NiCd TERMINAL VOLTAGE (V)
NiCd CELL CAPACITY (mA Hr)
OUTPUT VOLTAGE, V
(V)
BAK
1559 G03
1559 G01
1559 G02
Boost Converter Switching
Duty Cycle
Normalized Fast Recharge
Current vs Temperature
Trickle Charge Multiplier Factor
1.005
1.000
0.995
0.990
0.985
0.980
0.975
100
80
60
40
20
0
10.5
10.4
10.3
10.2
10.1
10.0
9.9
0.970
0.965
9.8
LTC1559-3.3
9.7
0.960
0.955
0.950
V
I
= 1.2V
BAT
PK
= 330mA
9.6
9.5
75
4
6
8
0.8
1.0
0
25
50
2
10
0
0.2 0.4 0.6
1.2 1.4 1.6 1.8 2.0
TEMPERATURE (°C)
OUTPUT VOLTAGE, V
(V)
NiCd BATTERY TRICKLE CURRENT (mA)
BAK
1559 G06
1559 G04
1559 G05
RESET Output Voltage
vs Supply Voltage
Fast Recharge Time (Assume
NiCd Battery Fully Exhausted)
RESET Output Voltage
vs Supply Voltage
60
50
40
30
20
10
0
6
5
4
3
2
1
0
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
LTC1559-5
LTC1559-3.3
4.55V
4.7V
3.12V
3V
64
128
256
512
0
2
3
4
5
6
0
2
3
4
1
1
BATTERY CAPACITY (mA Hr)
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
1559 G07
1559 G08
1559 G09
4
Linear [ Linear ]
