FEATURES

? Dynamic Headroom Control Output to

Maximize Efficiency

? 6 Channels Current Regulated LED Driver

? High Precision Analog Dimming Control

Interface

? 4 Individual PWM Dimming Control Input

? Dimming Control via Digital Data Bus

? Built-In Maximum MOSFET Power Limiting

Mechanism

? Allows Cascade Operation to Extend the

Output Channels

? Fault Indicator Output

? Thermal Shutdown

? UVLO With Hysteresis

? 48L WQFN Package

KEY SPECIFICATIONS

? Wide supply voltage range (12V-95V)

? Thermal fold-back dimming control

? DHC regulates the lowest MOSFET drain

voltage to 1V

APPLICATIONS

? Streetlights

? Solid State Lighting Solutions

DESCRIPTION

The LM3463 is a six channel linear LED driver with

Dynamic Headroom Control (DHC) interface that is

specialized for high power LED lighting applications.

The variation of the output current of every output

channel in the temperature range of -40°C to 125°C

is well controlled to less than ±1%. The output current

of every channel is accurately matched to each other

with less than ± 1% difference as well.

By interfacing the LM3463 to the output voltage

feedback node of a switching power supply via the

DHC interface, the system efficiency is optimized

automatically. The dynamic headroom control circuit

in the LM3463 minimizes power dissipation on the

external MOSFETs by adjusting the output voltage of

the primary switching power supply according to the

changing forward voltage of the LEDs. Comprising

the advantages of linear and switching converters,

the LM3463 delivers accurately regulated current to

LEDs while maximizing the system efficiency.

The dimming control interface of the LM3463 accepts

both analog and PWM dimming control signals. The

analog dimming control input controls the current of

all LEDs while the PWM control inputs control the

dimming duty of output channels individually.