List of Recommended External Components

Symbol

Symbol Explanation

Value

Unit

Type

C

VDD1

V

1

µF

Ceramic, X7R

C

VDD2

V

1

µF

Ceramic, X7R

C

OUT

Output capacitor from FB to GND

10

µF

Ceramic, X7R/Y5V

C

IN

Input capacitor from Battery Voltage to GND

10

µF

Ceramic, X7R/Y5V

C

VDDIO

V

1

µF

Ceramic, X7R

C

VDDA

Internal LDO output capacitor, between V

1

µF

Ceramic, X7R

RT

Oscillator Frequency Bias Resistor

82

k

Ω

1% (Note 16)

RDO

DO output pull-up resistor

100

k

Ω

C

VREF

Reference Voltage Capacitor, between V

100

nF

Ceramic, X7R

L

BOOST

Boost converter inductor

10

µH

Shielded, Low ESR, I

D

OUT

Rectifying Diode, V

0.3

V

Schottky Diode

RGB

RGB LED

User Defined

(See Application Note AN-1293 for resistor size calculation)

R

Current Limit Resistors

LEDs

White LEDs

Note 16: Resistor RT tolerance change will change the timing accuracy of the RGB block. Also the boost converter switching frequency will be affected.

Control Registers

All user accessible control registers and register bits are shown in the following table.

ADDR

SETUP

D7

D6

D5

D4

D3

D2

D1

D0

00H

Control register rgb_pwm rgb_start

cycle[1]

cycle[0]

rsw

gsw

bsw

pfm_mode

01H

ron

ron[6]

ron[5]

ron[4]

ron[3]

ron[2]

ron[1]

ron[0]

02H

roff

roff[6]

roff[5]

roff[4]

roff[3]

roff[2]

roff[1]

roff[0]

03H

gon

gon[6]

gon[5]

gon[4]

gon[3]

gon[2]

gon[1]

gon[0]

04H

goff

goff[6]

goff[5]

goff[4]

goff[3]

goff[2]

goff[1]

goff[0]

05H

bon

bon[6]

bon[5]

bon[4]

bon[3]

bon[2]

bon[1]

bon[0]

06H

boff

boff[6]

boff[5]

boff[4]

boff[3]

boff[2]

boff[1]

boff[0]

07H

rslope, rduty

rslope[3]

rslope[2]

rslope[1]

rslope[0]

rduty[3]

rduty[2]

rduty[1]

rduty[0]

08H

gslope, gduty

gslope[3] gslope[2] gslope[1]

gslope[0]

gduty[3]

gduty[2]

gduty[1]

gduty[0]

09H

bslope, bduty

bslope[3] bslope[2] bslope[1]

bslope[0]

bduty[3]

bduty[2]

bduty[1]

bduty[0]]

0AH

wled current 1

wled1[7]

wled1[6]

wled1[5]

wled1[4]

wled1[3]

wled1[2]

wled1[1]

wled1[0]

0BH

enables

overflow

nstby

en_boost

en_flash

en_ambave

en_ambadc

en_4led

en_2led

0CH

Amb. Light data

ain[7]

ain[6]

ain[5]

ain[4]

ain[3]

ain[2]

ain[1]

ain[0]

0DH

boost output

boost[7]

boost[6]

boost[5]

boost[4]

boost[3]

boost[2]

boost[1]

boost[0]

2AH

wled current 2

wled2[7]

wled2[6]

wled2[5]

wled2[4]

wled2[3]

wled2[2]

wled2[1]

wled2[0]

2BH

ext pwm enable

en_redpwm en_greenpwm en_bluepwm en_4ledpwm en_2ledpwm

Default value of each register is 0000 0000 except the following

— boost output default is 0000 0111 = 07h (4.55V).

— enables default is x010 0000 = 20h (boost enabled)

— ext_pwm_enable default is 0001 1100 = 1Ch (RGB_EN control enabled for color outputs)

Register 0Ch all bits (ain[7:0]) and bit D7 in register 0Bh (overflow) are read only. All other bits are read-write.

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