LTC1479 Datasheet, PDF (17/24 Pages) Linear Technology – PowerPath Controller for Dual Battery Systems

LTC1479
APPLICATIONS INFORMATION
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.
POWER
MANAGEMENT
µP
BAT1
CHGMON
LTC1479
BAT2 GG SG GH SH ^DCIN
BAT1
4 Li-ION
BATTERY
PACK
BAT2
4 Li-ION
BATTERY
PACK
TO SW C/D
TO SW E/F
+
CBAT1
–
47µF
SW G
Si9926DY
+
CBAT2
–
47µF
SW H
Si9926DY
330Ω
0.1µF
TO
SW A/B
C6
10µF
CERAMIC
RPROG
11k
1%
R1
100k
1%
Q1
2N7002
R2
300Ω
C1
1µF
R3
1k
C2
0.1µF
D1
MBRS140T
V_{CC SW}
PROG
VC BOOST
LT1510
SENSE
GND OVP
BAT
C3
0.22µF
D3
1N4148
DC INPUT
(FROM AC
ADAPTOR)
D2
MBRS140T
L1*
33µH
R4
649k
0.25%
R5
115k
0.25%
*COILTRONICS CTX33-2
CURRENT CONTROL
FROM POWER
MANAGEMENT µP
(CHARGER OUTPUT)
+
C_CHG
22µF
TANT
1479 F10
Figure 10. Interfacing to the LT1510 Constant-Voltage/Constant-Current Battery Charger
POWER
MANAGEMENT
µP
BAT1
CHGMON
LTC1479
DCIN
BAT2 GG SG GH SH
BAT1
4 Li-ION
BATTERY
PACK
TO SW C/D
TO SW E/F
+
+
CBAT1
47µF
SW G
–
Si9926DY
+
BAT2
4 Li-ION
BATTERY
PACK _–
+
CBAT2
47µF
SW H
Si9926DY
330Ω
0.1µF
C4
+
10µF
CERAMIC
R_S4
0.05Ω
D1
MBRS340T
C12
C5
1µF
10µF
R3
500Ω
R4
5k
DC INPUT
(FROM AC
ADAPTOR)
TO
SW A/B
RPROG
4.93k
1%
C1
1µF
R1
500Ω
R2
1k
C2
0.33µF
CLN V_CC CLP
PROG
UV
VC
SW
C3
200pF
COMP1 BOOST
LT1511
SPIN
Q1
2N7002
GND OVP
BAT SENSE
R_S2
200Ω
1%
(CHARGER OUTPUT)
R_S1
0.033Ω
R_S3
200Ω
1%
R5
6.8k
D2
MBRS340T
C6
0.47µF _L1
D3 ^20µH
MBR0540T
R6
649k
0.25%
C7
50pF
R7
115k
0.25%
1479 F11
CURRENT CONTROL
FROM POWER
MANAGEMENT µP
+ C_CHG
22µF
TANT
Figure 11. Interfacing to the LT1511 Constant-Voltage/Constant-Current Battery Charger with Input Current Limiting
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