1.2MHz, Low-Cost,

High-Performance Chargers

_______________________________________________________________________________________

7

Typical Operating Characteristics

°C, unless otherwise noted.)

IINP DC ERROR

vs. SYSTEM CURRENT

SYSTEM CURRENT (A)

4

3

12

-8

-6

-4

-2

0

2

4

6

8

10

-10

05

IINP ERROR

vs. SYSTEM CURRENT

SYSTEM CURRENT (A)

4.0

3.5

2.5 3.0

1.0 1.5 2.0

0.5

-8

-6

-4

-2

0

2

4

6

8

10

-10

04.5

ISET PWM DUTY-CYCLE CHANGE

DUTY CYCLE

0.8 0.9

0.1 0.2 0.3 0.4 0.5 0.6 0.7

0.5

1.0

1.5

2.0

2.5

3.0

0

01.0

ISET PWM DUTY-CYCLE CHANGE

DUTY CYCLE

80

90

10 20

30 40 50 60 70

0.5

1.0

1.5

2.0

2.5

3.0

3.5

0

0100

ISET PWM FREQUENCY SWEEP

FREQUENCY (kHz)

600

700

100

200 300

400

500

0.5

1.0

1.5

2.0

2.5

3.0

0

0

800

DUTY CYCLE = 75%

DUTY CYCLE = 25%

BATTERY VOLTAGE-SETTING ERROR

VCTL (V)

3.0

3.5 4.0

0.5 1.0 1.5 2.0 2.5

-0.5

-0.4

-0.3

-0.2

-0.1

0

-0.6

04.5

SYSTEM LOAD TRANSIENT

MAX17005B toc07

200

μs/div

SYSTEM

CURRENT

5A/div

CHARGING

CURRENT

5A/div

INDUCTOR

CURRENT

5A/div

EFFICIENCY

vs. CHARGE CURRENT

CHARGE CURRENT (A)

2.5

3.0

3.5

0.5

1.0

1.5

2.0

70

65

75

80

85

95

90

100

60

04.0

2 CELLS

3 CELLS

4 CELLS