MV1012SC

4

1. Overview

1.1 Features

The MV1012SC is an LED driver IC that uses an external power supply and can consist solely of low-voltage pins.

Omitting the auxiliary winding enables a single power supply configuration, and quasi-resonant operation in critical

conduction mode raises efficiency and lowers noise.

In general critical conduction mode, the switching frequency increases when the dimming ratio decreases. This

increases switching losses and imposes limitations on the lowest dimming ratios, disadvantageously. When the dimming

ratio decreases, the MV1012SC automatically switches from critical conduction mode to discontinuous conduction mode.

This prevents the switching frequency increasing, reduces switching losses, and achieves smooth and deep dimming free

voltage (Vth_REF_sp).

The MV1012SC has the following features:



Allows quasi-resonant operation without auxiliary winding.



Quasi-resonant operation in critical conduction mode helps achieve low input change, raises efficiency, and lowers

noise.



Off-time modulation enables deep dimming (1% or less).



Allows PWM dimming input and linear dimming input.





Allows LED open-circuit protection using auxiliary winding.



Features UVLO, and LED short-circuit protection.



Allows configuration solely of low voltage pins using an external start-up circuit.

1.2 Block diagram

Gate

Drive

Level

Ｓhift

Bandgap

Vcc

Vreg=5V(typ）

OVP

ON

Trigger

Restart

Timer

Dimming

Control

Logic

OFF

Trigger

UVLO

Vcc

LEB

STOP Signal

Vth_CS

OVP

S

R

Q

UVLO

Latch Signal

Ｚｅｒｏ Ｃｕｒｒｅｎｔ

Ｄｅｔｅｃｔｉｏｎ

Vth_REF_sp

STOP Signal

CAT.No.1A0602-1E