MAGNETIC BOOST DC/DC CONVERTER ELECTRICAL CHARACTERISTICS

Limits in standard typeface are for T

C

= 100 nF, L

Symbol

Parameter

Conditions

Min

Typ

Max

Units

I

LOAD

Load Current

(Note 10)

3.2V

≤ V

IN

≤ 4.5V

V

670

mA

V

OUT

Output Voltage Accuracy

(FB pin)

3.2V

≤ V

IN

≤ 4.5V

V

active load off

−3

+3

%

Output Voltage

(FB Pin)

3.0V

≤ V

IN

≤ (5.0V+V

active load off

5.0

V

V

RDS

ON

Switch ON Resistance

V

0.20

0.4

Ω

f

PWF

PWM Mode Switching

Frequency

RT =82k

Ω

FREQ_SEL (bit) = 1

FREQ_SEL (bit) = 0

2.0

1.0

MHz

Frequency Accuracy

3.2V

≤ V

DD1,2

≤ 4.5V

RT =82k

Ω

−6

-9

+9

%

t

PULSE

Switch Pulse Minimum

Width

no load

25

ns

t

STARTUP

Startup Time

10

ms

I

CL_OUT

SW1+ SW2 current limit

1.7

A

Note 10: Specified currents are the worst case currents. If input voltage is larger or output voltage is smaller, current can be increased according to graph "Boost

Maximum Output Current".

BOOST STANDBY MODE

User can set the boost converter to STANDBY mode by

writing the register bit EN_BOOST low when there is no load

to avoid idle current consumption. When EN_BOOST is

written high, the converter starts in low current PWM (Pulse

Width Modulation) mode for 10 ms and then goes to normal

PWM mode.

BOOST CONTROL REGISTERS

User can control the boost output voltage and the switching

frequency according to the following tables.

Boost Output Voltage

[3:0] Register

Boost Output Voltage

(Typical)

0000

4.55V

0001

4.70V

0011

4.85V

0111

5.00V

FREQ_SEL Bit

Boost Switching

Frequency

(Typical)

0

1.0 MHz default

1

2.0 MHz

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