17

LTC1479

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

+

+

47

µF

47

µF

DC INPUT

(FROM AC

ADAPTOR)

D1

MBRS340T

R1

500

Ω

C2

0.33

µF

C1

1

µF

PROG

4.93k

1%

0.05

Ω

C3

200pF

SW

UV

BOOST

COMP1

SPIN

BAT

SENSE

GND

C6

0.47

µF

C7

50pF

C12

1

µF

C5

10

µF

D3

MBR0540T

L1

20

µH

D2

MBRS340T

LT1511

C4

10

µF

CERAMIC

0.1

µF

330

Ω

+

22

µF

TANT

+

(CHARGER OUTPUT)

Q1

2N7002

R2

1k

CURRENT CONTROL

FROM POWER

MANAGEMENT

µP

+

–

R6

649k

0.25%

R5

6.8k

R4

5k

R3

500

Ω

R7

115k

0.25%

200

Ω

1%

200

Ω

1%

0.033

Ω

OVP

CLP

CLN

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

+

+

47

µF

47

µF

DC INPUT

(FROM AC

ADAPTOR)

D1

MBRS140T

R2

300

Ω

C1

1

µF

PROG

11k

1%

R3

1k

C2

0.1

µF

SW

BOOST

SENSE

BAT

GND

C3

0.22

µF

0.1

µF

D3

1N4148

L1*

33

µH

D2

MBRS140T

LT1510

C6

10

µF

CERAMIC

+

22

µF

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

Ω

+

–

POWER

MANAGEMENT

µP

BAT1

BAT2 GG SG GH SH

CHGMON

DCIN

LTC1479

Figure 10. Interfacing to the LT1510 Constant-Voltage/Constant-Current Battery Charger