ACT2801/ACT2801C
Rev 2, 15-Apr-14
from IOST pin to AGND as shown in Figure 11. The
boost output current is estimated as the following
equation:
2
RIOST (kΩ )
Rcs (mΩ )
IIOST (A) = ( A)×
(5)
3
Figure 7. Input current limit setting circuit
Input current limit at various resistor curve is shown
in Figure 8.
3.0
2.5
2.0
1.5
Figure 11. Boost output current setting circuit
Figure 12 gives out boost output current with
various RIOST
.
1.0
0.5
1.9
1.6
0
0.7 1.2 1.7 2.2 2.7 3.2 3.7 4.2 4.7
RILIM (kΩ)
Figure 8. Input current limit setting
1.3
1.0
0.7
Battery Fast Charge Current
Battery fast charge current is set by a resistor
connected from ICST pin to AGND as shown in
Figure 9. Figure 10 gives out different fast charge
current with various RICST. The battery fast charge
current is estimated as the following equation:
0.4
20
40
60
80
100
120
140
RIOST (kΩ)
Figure 12. Boost output current setting
Battery Impedance Compensation
RICST (kΩ )
Rcs(mΩ )
Ic(A) =1.25(A)×
(4)
An external resistor is used to set the impedance
from 40mΩ to 500mΩ as shown in Figure 13. RIMC
is corresponding to battery impedance. Higher RIMC
gives higher compensation voltage which is
positively proportional to battery charge/discharge
current.
Select RIMC based on battery impedance:
25 × R (mΩ )
Rcs (m Ω )
(6)
(7)
R
IMC(kΩ ) =
Figure 9. Battery fast charge current setting circuit
VBAT(V ) = BAT(V )−IBAT(A)×R(mΩ )×10-3
2.1
1.8
1.5
1.2
0.9
0.6
0.3
0
0
10
20
30
40
50
60
70
80
RICST (kΩ)
Figure 13. Battery impedance compensation setting circuit
Figure 10. Battery fast charge current setting
The battery impedance as shown in the table 4
according to the RIMC and Rcs:
Boost Output Constant Current
Boost output current is set by a resistor connected
Innovative PowerTM
- 13 -
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