Datasheet

ƒ
o
+
1
2p L
OUT
C
OUT
Ǹ
C
OUT
+
1
4p
2
ƒ
o
2
L
OUT
C
OUT
+
1
4p
2
(16 10
3
)
2
(10 10
*6
)
C
OUT
+ 9.89 mF
R
SNS
+
V
RSNS
I
CHARGE
R
SNS
+
100 mV
1.33 A
R
SNS
+ 0.075 W
P
RSNS
+ I
CHARGE
2
R
SNS
P
RSNS
+ 1.33
2
0.1
P
RSNS
+ 176.9 mW
R
ISET1
+
K
ISET1
V
ISET1
R
SNS
I
CHARGE
R
ISET1
+
1000 1.0
0.1 1.33
R
ISET1
+ 7.5 kW
R
ISET2
+
K
ISET2
V
ISET2
R
SNS
I
PRECHARGE
R
ISET2
+
1000 0.1
0.1 0.133
R
ISET2
+ 7.5 kW
bq24100, bq24103, bq24103A
bq24104, bq24105, bq24108, bq24109
bq24113, bq24113A, bq24115
SLUS606O –JUNE 2004–REVISED MARCH 2010 www.ti.com
2. Determine the output capacitor value (
OUT
) using 16 kHz as the resonant frequency:
(16)
Use standard value 10 mF, 25V, X5R, ±20% ceramic capacitor (i.e., Panasonic 1206 ECJ-3YB1E106M
3. Determine the sense resistor using the following equation:
(17)
In order to get better current regulation accuracy (±10%), let V
RSNS
be between 100 mV and 200 mV. Use
V
RSNS
= 100 mV and calculate the value for the sense resistor.
(18)
This value is not standard in resistors. If this happens, then choose the next larger value which in this case is
0.1Ω. Using the same equation (15) the actual V
RSNS
will be 133mV. Calculate the power dissipation on the
sense resistor:
(19)
Select standard value 100 mΩ, 0.25W 0805, 1206 or 2010 size, high precision sensing resistor. (i.e., Vishay
CRCW1210-0R10F)
4. Determine ISET 1 resistor using the following equation:
(20)
Select standard value 7.5 kΩ, 1/16W ±1% resistor (i.e., Vishay CRCWD0603-7501-F)
5. Determine ISET 2 resistor using the following equation:
(21)
Select standard value 7.5 kΩ, 1/16W ±1% resistor (i.e., Vishay CRCWD0603-7501-F)
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