LT3476 - High Current Quad Output LED Driver
Datasheet Documentation
Datasheet
Reliability Data
LT Journal
Press Release
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Overview

Features

  • True Color PWM Dimming Delivers Up to 5000:1 Dimming Ratio (In Boost Configuration)
  • LED Current Regulation with High-Side Sense
  • VADJ Pin Accurately Sets LED Current Sense Threshold Over Range 10mV to 120mV
  • Four Independent Driver Channels with 1.5A, 36V Internal NPN Switches
  • Frequency Adjust Pin: 200kHz to 2MHz
  • High Efficiency Conversion = Up to 96%
  • Open LED Protection
  • Low Shutdown Current < 10μA
  • Wide VIN Range: 2.8V to 16V
  • Thermally Enhanced, 38-Lead, 5mm × 7mm QFN Package

Typical Application

LT3476 Typical Application
LT3476 Typical Application

Description

The LT3476 is a quad output DC/DC converter designed to operate as a constant-current source for driving high current LEDs. A fixed frequency, current mode architecture results in stable operation over a wide range of supply and output voltages. A frequency adjust pin allows the user to program switching frequency between 200kHz and 2MHz to optimize efficiency and external component size. The LT3476 senses output current at the high side of the LED. High side current sensing is the most flexible scheme for driving LEDs, allowing buck, boost or buckboost configurations. Each current monitor threshold is trimmed to within 2.5% at the full scale of 105mV. With an external sense resistor, the user programs the output current range of each channel. Each of the four regulators is independently operated by that channel’s PWM signal. This PWM feature allows precise adjustment of the color mixing or dimming ratio of the LED source. Dimming ratios up to 1000:1 can be achieved.
Packaging

5x7 QFN-38

LT3476 Package Drawing
Order Info

Package Variations and Pricing

Part Number Package Pins Temp Price
(1-99)		 Price
(1k)*
LT3476EUHF#PBF QFN 38 E $6.63 $4.64
LT3476EUHF#TRPBF QFN 38 E $4.70
LT3476IUHF#PBF QFN 38 I $7.63 $5.34
LT3476IUHF#TRPBF QFN 38 I $5.40
LT3476EUHF QFN 38 E $13.26 $9.28
LT3476EUHF#TR QFN 38 E $9.40
* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.


Part Number Description Price Documentation
DC976A LT3476EUHF Demo Board | Quad Buck Mode LED Driver, PVIN ≤ 33V, Up to 27VLED @ 350mA or 1.05A $150.00