Boost Converter Topology

20080528

Magnetic Boost DC/DC Converter Electrical Characteristics

Symbol

Parameter

Conditions

Min

Typ

Max

Units

I

LOAD

Load Current

3.0V

≤ V

IN

≤ 4.5V

V

0

300

mA

V

FB

Output Voltage

Accuracy (FB Pin)

1mA

≤ I

LOAD

≤ 300 mA

3.0V

≤ V

IN

≤

V

V

−5

+5

%

Voltage at FB Pin

(Boost Converter

Output Voltage)

1mA

≤ I

LOAD

≤ 300 mA

V

(SCHOTTKY)

5V

1mA

≤ I

LOAD

≤ 300 mA

V

V

V

RDS

ON

Switch ON Resistance

V

0.5A

0.4

0.7

Ω

f

PWF

PWM Mode Switching

Frequency

RT=82k

Ω

1

MHz

Frequency Accuracy

2.65

≤ V

DD1, 2

≤ 2.9

−6

%

RT=82k

Ω

−9

+9

t

STARTUP

Startup Time

25

ms

I

CL_OUT

SW Pin Current Limit

670

800

915

mA

530

995

Boost Standby Mode

User can set the Boost Converter to STANDBY mode by writing the register bit EN_BOOST low. When EN_BOOST is written

high, the converter starts for 10 ms in PFM mode and then goes to PWM mode.

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