Typical operating characteristics (continued) – Rainbow Electronics MAX1873 User Manual
Page 7
MAX1873
Simple Current-Limited Switch-Mode
Li+ Charger Controller
_______________________________________________________________________________________
7
50
60
80
70
90
100
MAX1873S (3-CELL)
EFFICIENCY vs. INPUT VOLTAGE
MAX1873 toc07
INPUT VOLTAGE (V)
EFFICIENCY (%)
12
20
16
24
28
V
BATT
= 10.5V
I
CHG
= 3A
50
60
80
70
90
100
16
20
18
22
24
26
28
MAX1873T (4-CELL)
EFFICIENCY vs. INPUT VOLTAGE
MAX1873 toc08
INPUT VOLTAGE (V)
EFFICIENCY (%)
V
BATT
= 14V
I
CHG
+ 3A
0
1.0
0.5
2.0
1.5
2.5
3.0
0
1.0
1.5
0.5
2.0
2.5
3.0
CHARGING CURRENT
vs. SYSTEM LOAD CURRENT
MAX1873 toc10
SYSTEM LOAD CURRENT (A)
CHARGING CURRENT (A)
4
8
6
12
10
16
14
18
0
50
75
25
100
125
150
4-CELL BATTERY VOLTAGE AND
CHARGING CURRENT vs. TIME
MAX1873 toc09
TIME (MINUTES)
BATTERY VOLTAGE (V)
BATTERY VOLTAGE
CHARGING CURRENT
CHARGING CURRENT (A)
0
1.0
0.5
2.0
1.5
3.0
2.5
3.5
Typical Operating Characteristics (continued)
(Circuit of Figure 1, V
DCIN
= V
CSSP
= V
CSSN
= 18V, V
ICHG/EN
= V
REF
, V
VADJ
= V
REF
/2. MAX1873R: V
BATT
= V
CSB
= 8.4V;
MAX1873S: V
BATT
= V
CSB
= 12.6V; MAX1873T: V
BATT
= V
CSB
= 16.8V; T
A
= +25°C, unless otherwise noted).