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Typical operating characteristics – Rainbow Electronics MAX1730 User Manual

Page 4

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MAX1730

50mA Regulated Step-Down Charge Pump
for 1.8V or 1.9V Logic

4

_______________________________________________________________________________________

Typical Operating Characteristics

(V

IN

= +3.6V, FB = GND, SHDN = IN, C

IN

= 1µF, C1 = C2 = 0.22µF, C

OUT

= 4.7µF, T

A

= +25°C, unless otherwise noted.)

0.1

10

1

100

1000

EFFICIENCY

vs. OUTPUT CURRENT

MAX1730 TOC01

OUTPUT CURRENT (mA)

EFFICIENCY (%)

100

90

80

70

60

0

10

30

20

50

40

V

IN

= 5.0V

V

IN

= 2.7V

V

IN

= 3.6V

V

IN

= 3.3V

50

65

60

55

70

75

80

85

90

95

100

2.5

3.5

3.0

4.0

4.5

5.0

5.5

EFFICIENCY vs. INPUT VOLTAGE

MAX1730 TOC02

INPUT VOLTAGE (V)

EFFICIENCY (%)

I

OUT

= 25mA

50

65

60

55

70

75

80

85

90

95

100

2.5

3.5

3.0

4.0

4.5

5.0

5.5

EFFICIENCY vs. INPUT VOLTAGE

MAX1730 TOC02

INPUT VOLTAGE (V)

EFFICIENCY (%)

I

OUT

= 50mA

0

20

10

40

30

60

50

70

2.0

3.0

3.5

2.5

4.0

4.5

5.0

5.5

INPUT CURRENT vs. INPUT VOLTAGE

MAX1730 TOC04

INPUT VOLTAGE (V)

INPUT CURRENT (

µ

A)

SHUTDOWN CURRENT

NO-LOAD

SUPPLY CURRENT

0.1

10

1

100

1000

OUTPUT VOLTAGE

vs. OUTPUT CURRENT

MAX1730 TOC05

OUTPUT CURRENT (mA)

OUTPUT VOLTAGE (V)

1.85

1.75

1.77

1.79

1.83

1.81

V

IN

= 5.0V

V

IN

= 2.7V

V

IN

= 3.3V

0

0.4

0.2

0.8

0.6

1.2

1.4

1.6

1.8

1.0

2.0

0

2

3

1

4

5

6

OUTPUT VOLTAGE vs. INPUT VOLTAGE

MAX1730 TOC06

INPUT VOLTAGE (V)

OUTPUT VOLTAGE (V)

I

OUT

= 0 to 50mA