Max8730 low-cost battery charger, Typical operating characteristics (continued) – Rainbow Electronics MAX8730 User Manual
Page 12
MAX8730
Low-Cost Battery Charger
12
______________________________________________________________________________________
Typical Operating Characteristics (continued)
(Circuit of Figure 1, adapter = 19.5V, V
BATT
= 12V, V
ICTL
= 2.4V, MODE > 1.8V, REFON = INPON = LDO, V
RELTH
= V
REF
/2, T
A
=
+25°C, unless otherwise noted.)
CHARGE CURRENT vs. TIME
TIME (h)
CHARGE CURRENT (A)
MAX8730 toc20
0
0.5
1.0
1.5
2.0
2.5
3.0
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
INITIAL CONDITION: 4 CELLS
10V BATTERY
FULL CHARGE = 16.8V
LDO LOAD REGULATION
I
LDO
(mA)
LDO ERROR (%)
MAX8730 toc21
0
10
20
30
40
50
-0.9
-0.8
-0.6
-0.4
-0.2
-0.7
-0.5
-0.3
-0.1
0
CHARGER DISABLED
BATTERY LEAKAGE CURRENT
vs. BATTERY VOLTAGE
BATTERY VOLTAGE (V)
BATTERY-LEAKAGE CURRENT (
µ
A)
MAX8730 toc19
0
3
6
9
12
15
18
0
100
200
300
400
500
REFON = INPON = 1
REFON = 0
INPON = 1
REFON = 1
INPON = 0
REFON = INPON = 0
ADAPTER QUIESCENT CURRENT
vs. ADAPTER VOLTAGE
ADAPTER VOLTAGE (V)
ADAPTER QUIESCENT CURRENT (mA)
MAX8730 toc18
0
5
10
15
20
25
0
0.5
1.0
1.5
2.0
2.5
3.0
BATTERY ABSENT
REFON = 1
INPON = 1
REFON = 0
INPON = 0
PEAK-TO-PEAK INDUCTOR CURRENT
vs. BATTERY VOLTAGE
BATTERY VOLTAGE (V)
PEAK-TO-PEAK INDUCTOR CURRENT (A)
MAX7830 toc16
0
3
6
9
12
15
18
0.5
0.9
0.7
1.1
1.5
1.3
1.7
1.9
2.1
2.3
2.5
EFFICIENCY vs. CHARGE CURRENT
CHARGE CURRENT (A)
EFFICIENCY (%)
MAX8730 toc17
0
1.0
2.0
3.0
3.5
0.5
1.5
2.5
4.0
60
70
80
90
100
4 CELLS
3 CELLS