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Typical operating characteristics (continued) – Rainbow Electronics MAX1708 User Manual

Page 6

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MAX1708

High-Frequency, High-Power, Low-Noise,
Step-Up DC-DC Converter

6

_______________________________________________________________________________________

1000

10,000

0

0.2

0.4

0.6

0.8

1.2

1.0

1.6

1.4

1.8

1

10

100

STARTUP VOLTAGE vs. LOAD CURRENT

(V

OUT

= 5V)

MAX1708 toc06a

LOAD CURRENT (mA)

STARTUP VOLTAGE (V)

T

A

= -40

°C

T

A

= +25

°C

T

A

= +85

°C

2.5

2.0

1.5

1.0

0.5

0

1

100

1000

10

10,000

STARTUP VOLTAGE vs. LOAD CURRENT

(V

OUT

= 3.3V)

MAX1708 toc06b

LOAD CURRENT (mA)

STARTUP VOLTAGE (V)

T

A

= -40

°C

T

A

= +25

°C

T

A

= +85

°C

2

1

0

-1

-2

-40

10

-15

35

60

85

SWITCHING FREQUENCY

vs. TEMPERATURE

MAX1708 toc07

TEMPERATURE (

°C)

FREQUENCY CHANGE (%)

V

OUT

= 3.3V

PLOT NORMALIZED TO 25

°C

4000

0

0.1

1

10

NOISE vs. FREQUENCY

MAX1708 toc08

FREQUENCY (MHz)

NOISE (

µ

V)

500

1000

2000

1500

3000

3500

2500

RESOLUTION = 1kHz

50

0

250

200

150

100

300

SWITCH CURRENT LIMIT

vs. SS/LIM RESISTANCE

MAX1708 toc09

SS/LIM RESISTANCE (k

Ω)

SWITCH CURRENT LIMIT (A)

1

2

0

4

5

3

6.0

5.5

5.0

4.5

4.0

-40

10

-15

35

60

85

SWITCH CURRENT LIMIT

vs. TEMPERATURE

MAX1708 toc10

TEMPERATURE (

°C)

SWITCH CURRENT LIMIT (A)

V

IN

= 3.3V, V

OUT

= 5V

1

µs/div

HEAVY SWITCHING WAVEFORM

V

OUT

AC-COUPLED

50mV/div

5V

4A

2A

5V

0

0

V

LX

5V/div

I

L

2A/div

MAX1708 toc11

100

µs/div

LINE TRANSIENT RESPONSE

V

OUT

AC-COUPLED

50mV/div

3.5V

3V

5V

V

IN

500mV/div

MAX1708 toc12

Typical Operating Characteristics (continued)

(Circuit of Figure 1, T

A

= +25°C, unless otherwise noted.)