Step-Down Converters

4

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Typical Operating Characteristics

EFFICIENCY vs. LOAD CURRENT

WITH 3.3V OUTPUT

LOAD CURRENT (mA)

100

10

1

60

70

80

90

100

50

40

0.1

1000

10,000

EFFICIENCY vs. LOAD CURRENT

WITH 2.5V OUTPUT

LOAD CURRENT (mA)

100

10

1

60

70

80

90

100

50

40

0.1

1000

10,000

EFFICIENCY vs. LOAD CURRENT

WITH 1.8V OUTPUT

LOAD CURRENT (mA)

100

10

1

60

70

80

90

100

50

40

0.1

1000

10,000

EFFICIENCY vs. LOAD CURRENT

WITH 1.0V OUTPUT (MAX1557)

LOAD CURRENT (mA)

100

10

1

60

70

80

90

100

50

40

0.1

1000

OUTPUT VOLTAGE

vs. LOAD CURRENT

LOAD CURRENT (mA)

1000

800

600

400

200

1.75

1.76

1.77

1.78

1.79

1.80

1.81

1.82

1.83

1.84

1.74

0

1200

°C

°C

°C

OUTPUT VOLTAGE vs. INPUT VOLTAGE

WITH 600mA LOAD

INPUT VOLTAGE (V)

5.0

4.5

4.0

3.5

3.0

1.780

1.781

1.782

1.783

1.784

1.785

1.786

1.787

1.788

1.789

1.779

2.5

5.5

°C

°C

°C

OUTPUT VOLTAGE vs. INPUT VOLTAGE

WITH NO LOAD

INPUT VOLTAGE (V)

5.0

4.5

4.0

3.5

3.0

1.804

1.805

1.806

1.807

1.808

1.809

1.810

1.811

1.812

1.803

2.5

5.5

°C

°C

°C

SUPPLY CURRENT vs. INPUT VOLTAGE

INPUT VOLTAGE (V)

5

4

3

2

2

4

6

8

10

12

14

16

18

20

0

16

HEAVY-LOAD SWITCHING WAVEFORMS

MAX1556/7 toc09

AC-COUPLED

10mV/div

2V/div

0

0

400ns

500mA/div