LT3492 - Triple Output LED Driver with 3000:1 PWM Dimming

Features

  • True Color PWM™ Dimming Delivers Up to 3000:1 Dimming Ratio
  • Built-In Gate Driver for PMOS LED Disconnect
  • Three Independent Driver Channels with 600mA, 60V Internal Switches
  • Operates in Buck, Boost, Buck-Boost Modes
  • CTRL Pin Accurately Sets LED Current Sense
  • Threshold Over a Range of 10mV to 100mV
  • Adjustable Frequency: 330kHz to 2.1MHz
  • Open LED Protection
  • Wide Input Voltage Range:
    Operation from 3V to 30V
    Transient Protection to 40V
  • Surface Mount Components
  • 28-Lead (4mm × 5mm) QFN and TSSOP Packages
Designed for Automotive and Transportation Applications
AEC-Q100 generic family data available for specific packages


Typical Application

LT3492 Typical Application
LT3492 Typical Application

Description

The LT3492 is a triple output DC/DC converter designed to operate as a constant-current source and is ideal for driving LEDs. The LT3492 works in buck, boost or buck-boost mode. The LT3492 uses a fixed frequency, current mode architecture resulting in stable operation over a wide range of supply and output voltages. A frequency adjust pin allows the user to program switching frequency between 330kHz and 2.1MHz to optimize efficiency and external component size.

The external PWM input provides 3000:1 LED dimming on each channel. Each of the three channels has a built-in gate driver to drive an external LED-disconnect P-channel MOSFET, allowing high dimming range. The output current range of each channel of the LT3492 is programmed with an external sense resistor.

The CTRL pin is used to adjust the LED current either for analog dimming or over-temperature protection.

Packaging

CAD Symbols and Footprints: The downloadable Zip file below contains the schematic symbol and PCB footprints.

For complete and up to date package information and drawings, please refer to our packaging page

Part Number Package Code Temp Package
Drawing
RoHS
LT3492EFE#PBF TSSOP-28 FE E 05-08-1663 (EB) Yes
LT3492EFE#TRPBF TSSOP-28 FE E 05-08-1663 (EB) Yes
LT3492EUFD#PBF 4x5 QFN-28 UFD E 05-08-1712 Yes
LT3492EUFD#TRPBF 4x5 QFN-28 UFD E 05-08-1712 Yes
LT3492IFE#PBF TSSOP-28 FE I 05-08-1663 (EB) Yes
LT3492IFE#TRPBF TSSOP-28 FE I 05-08-1663 (EB) Yes
LT3492IUFD#PBF 4x5 QFN-28 UFD I 05-08-1712 Yes
LT3492IUFD#TRPBF 4x5 QFN-28 UFD I 05-08-1712 Yes


LT3492 Package Drawing
LT3492 Package Drawing

Order Info

  • Part numbers ending in PBF are lead free. Solder plated terminal finish (SnPb) versions are non-standard and special terms and conditions and pricing applies if available. Please contact LTC marketing for information.
  • Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
  • Please refer to our general ordering information or the product datasheet for more details

Package Variations and Pricing

Part Number Package Temp Price
(1-99)
Price
(1k)*
RoHS
LT3492EFE#PBF TSSOP-28 E $5.50 $3.85 Yes
LT3492EFE#TRPBF TSSOP-28 E $3.91 Yes
LT3492EUFD#PBF 4x5 QFN-28 E $5.29 $3.70 Yes
LT3492EUFD#TRPBF 4x5 QFN-28 E $3.76 Yes
LT3492IFE#PBF TSSOP-28 I $6.47 $4.53 Yes
LT3492IFE#TRPBF TSSOP-28 I $4.59 Yes
LT3492IUFD#PBF 4x5 QFN-28 I $6.22 $4.35 Yes
LT3492IUFD#TRPBF 4x5 QFN-28 I $4.41 Yes
Buy NowRequest Samples
* 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
DC1405A LT3492EFE Demo Board | Boost/ Buck-Boost Triple Output LED Driver, 8V ≤ VIN ≤ 40V, VLED = 54V @ 61mA (x3) $125.00
Buy Now
Click here to view our complete list of demo boards

Designed for Automotive and Transportation Applications

Please contact your local sales representative for more information regarding reliability reports and AEC-Q100 data or to inquire about parts that are not included. For more information, view our Automotive and Transportation page

Part Number Package Temp Price
(1-99)
Price
(1k)*
RoHS
LT3492IFE#PBF TSSOP-28 I $6.47 $4.53 Yes
LT3492IFE#TRPBF TSSOP-28 I $4.59 Yes
LT3492IUFD#PBF 4x5 QFN-28 I $6.22 $4.35 Yes
LT3492IUFD#TRPBF 4x5 QFN-28 I $4.41 Yes
Buy NowRequest Samples
* 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.

Applications

  • RGB Lighting
  • Billboards and Large Displays
  • Automotive and Avionic Lighting
  • Constant-Current Sources

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Design Tools

LTspice

LTspice® software is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. Click here to download LTspice

To launch a ready to run LTspice demonstration circuit for this part:

  • Step 1: If you have not installed LTspice on this computer, download and install LTspice
  • Step 2: Once LTspice is installed, click on the link(s) below to launch the simulation
  • Step 3: If LTspice does not automatically open after clicking the link above, you can instead run the simulation by right clicking on the link and selecting "Save Target As." After saving the file to your computer, start LTspice and open the demonstration circuit by selecting 'Open' from the 'File' menu

To explore other ready to run LTspice demonstration circuits, please visit our Demo Circuits Collection.

Models for the following parts are available in LTspice:
LT3492

Technical Support