User's Guide
SNVA642 – May 2012
AN-2255 LM3463 Evaluation Board
The LM3463 is a 6-channel linear LED driver with Dynamic Headroom Control (DHC) designed to drive six
strings of high brightness LEDs at maximum supply voltage up to 95V. Each output channel of the
LM3463 evaluation board is designed to deliver 200 mA of LED driving current. The LED turn on voltage
is set to 48V by default, thus the board is able to deliver up to 57.6W total output power. The six output
channels are divided into 4 individual groups to facilitate average LED current control by means of PWM
dimming. The PWM dimming control interface of the LM3463 can accept standard TTL level PWM signals,
analog voltage or serial data to control the dimming duty of the four LED groups individually. The analog
dimming control interface accepts an analog control voltage in the range from 0V to 2.5V to adjust the
reference voltage of the linear current regulators, which enables true LED current adjustment. This
evaluation board is designed to be connected to an external primary power supply. Using three connection
wires, the VIN, GND and VFB, the dynamic Headroom Control (DHC) circuit of the LM3463 adjusts the
output voltage of the primary power supply to maximize system efficiency.
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AN-2255 LM3463 Evaluation Board
SNVA642 – May 2012
Copyright © 2012, Texas Instruments Incorporated