Description

The LC5546AD and LC5546LD are isolated LED

drivers in which a power MOSFET and a control IC are

highly integrated.

The IC provides the systems that can comply with the

harmonics standard (IEC61000-3-2 Class C) in all

conditions, including a light load condition. These

systems, moreover, can be achieved without an input

electrolytic capacitor.

The IC employs the average current and quasi-resonant

controls: the average current control realizes high power

factors, whereas the quasi-resonant control contributes to

high efficiency and low noise.

Having a rich set of protection features, the IC can

provide and more cost-effective power supply systems

with fewer external components.

Features

● Built-in On-time Control Circuit

(High Power Factor Achieved by Average Current

Control)

● Built-in Startup Circuit

(Reduced Numnber of External Components)

● Soft Start Function

(Startup Stress Reduction for Power MOSFET and

Secondary Rectifier Diode)

● Bias Assist Function

(Improved Startup Performance, VCC Voltage Drop

Suppresion in Operation, Reduced Capacitance of

VCC Pin Capacitor)

● Leading Edge Blanking Function

● Built-in Maximum On-time Limitation Function

● Protections Include:

Overcurrent Protection (OCP): Pulse-by-Pulse

VCC Pin Overvoltage Protection (VCC_OVP)

OCP Pin Overvoltage Protection (OCP_OVP)

OVP Pin Overvoltage Protection (OVP_OVP)

Overload Protection (OLP)

Thermal Shutdown (TSD)

Applications

● LED Lighting Equipment

● LED Bulbs