Limits in standard typeface are for T

(−40˚C

≤ T

A

≤ +85˚C). Unless otherwise noted, specifications apply to Figure 1 with: V

C

Symbol

Parameter

Conditions

Min

Typ

Max

Units

RDS

ON

Switch ON Resistance

V

0.4

0.7

Ω

f

PWF

PWM Mode Switching

Frequency

RT=82k

Ω

freq_sel[2:0] = 1XX

2.0

MHz

Frequency Accuracy

2.7

≤ VDD

1,2

≤ 2.9

−6

%

RT=82k

Ω

−9

+9

t

PULSE

Switch Pulse Minimum

Width

No Load

25

ns

t

STARTUP

Startup Time

15

ms

I

CL_OUT

SW Pin Current Limit

700

800

900

mA

500

1000

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 PFM (Pulse Frequency Modulation) mode for

10 ms and then goes to PWM (Pulse Width Modulation ) mode. All RGB outputs are off during the 10 ms delay.

Boost Output Voltage Control

User can control the boost output voltage by eight-bit boost output voltage register according to the following table.

BOOST[7:0]

Register 0D’h

BOOST Output

Voltage

(typical)

Binary

Hex

0000 0000

00

4.10

0000 0001

01

4.25

0000 0011

03

4.40

0000 0111

07

4.55

0000 1111

0F

4.70

BOOST[7:0]

Register 0D’h

BOOST Output

Voltage

(typical)

Binary

Hex

0001 1111

1F

4.85

0011 1111

3F

5.00 Default

0111 1111

7F

5.15

1111 1111

FF

5.30

Boost Frequency Control

The register ‘boost frequency’ has address 0C’h. The default value after reset is 07’h. ‘x’ means don’t care.

FREQ_SEL[2:0]

Frequency

1xx

2.00 MHz

01x

1.67 MHz

FREQ_SEL[2:0]

Frequency

001

1.00 MHz

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