MP3385A – 4-STRING WLED CONTROLLER WITH I

MP3385A Rev. 1.01

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17

8/29/2017

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Table 1: Dimming Mode Register

Addr: 0x00

Bit

Bit Name

Access

Default

Description

7:4

LED4:0

RW

1111b

LED current source enable bits. LED1/2/3/4 controls the internal

LED current sources, respectively.

LED1: LED current source 1

1 = enabled

0 = disabled

LED2: LED current source 2

1 = enabled

0 = disabled

LED3: LED current source 3

1 = enabled

0 = disabled

LED4: LED current source 4

1= enabled

0 = disabled

3

NA

RW

NA

N/A

2

INTERFACE

RW

0b

Dimming input interface set bit.

0 = dimming control by PWM input signal

1 = dimming control by I

1:0

MODE1:0

RW

00b

Dimming mode setting bits.

00 = PWM mode. The LED current duty cycle directly follows

the PWM input signal duty cycle when INTERFACE = 0. The IC

works in internal PWM dimming mode, and the LED current

duty cycle is set by the internal registers 03H and 04H when

INTERFACE = 1. The internal dimming frequency is fixed at

23kHz.

01 = Analog dimming mode. The LED current amplitude follows

the duty cycle of the input PWM signal when INTERFACE = 0

and follows the internal register value of 03H and 04H if

INTERFACE = 1.

10 = Mixed dimming mode. When the dimming duty cycle is

larger than the 25% threshold, the IC works in analog dimming

mode. Otherwise, the IC works in PWM dimming mode.

11 = Mixed dimming mode. When the dimming duty cycle is

larger than the 50% threshold, the IC works in analog dimming

mode. Otherwise, the IC works in PWM dimming mode.