ISL6257 Datasheet, PDF (7/22 Pages) Intersil Corporation – Highly Integrated Narrow VDC Battery Charger for Notebook Computers

ISL6257
Typical Operating Performance DCIN = 20V, 4S2P Li-Battery, T_A = +25°C, unless otherwise noted. (Continued)
ADAPTER REMOVAL
SGATE-CSIP
2V/div
SYSTEM BUS
VOLTAGE
10V/div
BGATE-CSIP
2V/div
INDUCTOR
CURRENT
2A/div
FIGURE 11. ADAPTER REMOVAL
BGATE-CSIP
2V/div
SYSTEM BUS
VOLTAGE
10V/div
ADAPTER INSERTION
SGATE-CSIP
2V/div
INDUCTOR
CURRENT
2A/div
FIGURE 12. ADAPTER INSERTION
FIGURE 13. ADAPTER INSERTION WITH A CHARGED
BATTERY
ISL6257 CHARGE CURVES
13
2.5
2.0
12
V battery
I battery
1.5
11
1.0
10
0.5
9
0.0
0
50
100
150
200
TIME (MINUTES)
FIGURE 15. BATTERY CHARGE VOLTAGE AND CURRENT
FIGURE 14. ADAPTER INSERTION WITH NO BATTERY AND A
2A SYSTEM LOAD
100%
Efficiency vs load current
95%
90%
85%
80%
75%
10Vin-8.4Vout
25Vin-8.4Vout
15Vin-12.6Vout
25Vin-12.6Vout
20Vin-16.8Vout
25Vin-16.8Vout
70%
0
2
4
6
8
10
12
Load Current (Amps)
FIGURE 16. EFFICIENCY VS LOAD CURRENT
7
FN9288.2
January 17, 2007