Datasheet

17
LTC1479
APPLICATIONS INFORMATION
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the charging battery through one of the N-channel switch
pairs, SW G or SW H. The charging battery voltage is
simultaneously connected through the CHGMON switch
in the LTC1479 to the top of the charger voltage resistor
divider, R4 and R5, for constant voltage charging. (See the
LT1510 data sheet for further detail.)
LT1511 Battery Charger Interface
The LT1511, 3A CC/CV battery charger with input current
limiting, is connected in a slightly different manner than
the LT1510 as illustrated in Figure 11.
Figure 11. Interfacing to the LT1511 Constant-Voltage/Constant-Current Battery Charger with Input Current Limiting
1479 F11
SW H
Si9926DY
SW G
Si9926DY
BAT1
4 Li-ION
BATTERY
PACK
BAT2
4 Li-ION
BATTERY
PACK
+
+
C
BAT1
47µF
C
BAT2
47µF
DC INPUT
(FROM AC
ADAPTOR)
V
CC
D1
MBRS340T
R1
500
C2
0.33µF
C1
1µF
PROG
R
PROG
4.93k
1%
R
S4
0.05
C3
200pF
V
C
SW
UV
BOOSTCOMP1
SPIN
BAT SENSE
GND
C6
0.47µF
C7
50pF
C12
1µF
C5
10µF
D3
MBR0540T
L1
20µH
D2
MBRS340T
LT1511
C4
10µF
CERAMIC
0.1µF
330
+
C
CHG
22µF
TANT
+
(CHARGER OUTPUT)
Q1
2N7002
R2
1k
CURRENT CONTROL
FROM POWER
MANAGEMENT µP
+
R6
649k
0.25%
R5
6.8k
R4
5k
R3
500
R7
115k
0.25%
R
S3
200
1%
R
S2
200
1%
R
S1
0.033
OVP
CLPCLN
TO SW C/D
TO SW E/F
TO
SW A/B
+
POWER
MANAGEMENT
µP
BAT1
BAT2
GG
SG
GH SH
CHGMON
DCIN
LTC1479
1479 F10
SW H
Si9926DY
SW G
Si9926DY
BAT1
4 Li-ION
BATTERY
PACK
BAT2
4 Li-ION
BATTERY
PACK
+
+
C
BAT1
47µF
C
BAT2
47µF
DC INPUT
(FROM AC
ADAPTOR)
V
CC
D1
MBRS140T
R2
300
C1
1µF
PROG
R
PROG
11k
1%
R3
1k
C2
0.1µF
V
C
SW
BOOST
SENSE
BAT
GND
C3
0.22µF
0.1µF
D3
1N4148
L1*
33µH
D2
MBRS140T
LT1510
C6
10µF
CERAMIC
+
C
CHG
22µF
TANT
(CHARGER OUTPUT)
Q1
2N7002
R1
100k
1%
CURRENT CONTROL
FROM POWER
MANAGEMENT µP
+
R4
649k
0.25%
R5
115k
0.25%
OVP
*COILTRONICS CTX33-2
TO SW C/D
TO SW E/F
TO
SW A/B
330
+
POWER
MANAGEMENT
µP
BAT1
BAT2
GG
SG
GH SH
CHGMON
DCIN
LTC1479
Figure 10. Interfacing to the LT1510 Constant-Voltage/Constant-Current Battery Charger