MP3378E

– 4-CHANNEL WLED CONTROLLER WITH BUCK CONVERTER

MP3378E Rev. 1.02

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11

5/26/2017

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Pin #

Name

Description

20

BST

Bootstrap for buck converter. A capacitor and a 47

Ω resistor connected between SW

and BST are required to form a floating supply across the high-side switch driver.

21

SYNC

Synchronization for buck converter. Apply a clock signal with a frequency higher than

250KHz. The frequency of the buck converter can be synchronized by an external clock.

The internal clock

’s rising edge is synchronized to the external clock’s falling edge.

22

ISENSE

Current sense input for WLED controller. During normal operation, ISENSE senses

current-mode control and also limits the inductor current during every switching cycle.

23

GATE

Power switch gate output for WLED controller. GATE drives the external power

N-channel MOSFET device.

24

VIN1

Supply input for WLED controller.

25

VCC1

Internal 6V linear regulator output for WLED controller. VCC1 provides a power

supply for the external MOSFET switch gate driver and the internal control circuitry.

Bypass VCC1 to GND with a ceramic capacitor.

26

COMP

Error amplifier output of WLED controller. Connect a capacitor and a resistor in

series to make the boost converter loop stable.

27

EN1

Enable input for WLED controller.

28

PWM

Input signal for PWM brightness control. The PWM pin should be used for dimming

and can not be used for turning on/off the WLED controller. Internally pull to GND if

PWM is floated.