LT3517 - Full-Featured LED Driver with 1.5A Switch Current

Features

  • 5000:1 True Color PWM™ Dimming Ratio
  • 1.5A, 45V Internal Switch
  • 100mV High Side Current Sense
  • Open LED Protection
  • Adjustable Frequency: 250kHz to 2.5MHz
  • Wide Input Voltage Range:
    Operation from 3V to 30V
    Transient Protection to 40V
  • Operates in Boost, Buck Mode and Buck-Boost Mode
  • Gate Driver for PMOS LED Disconnect
  • Constant-Current and Constant-Voltage Regulation
  • CTRL Pin Provides 10:1 Analog Dimming
  • Low Shutdown Current: <1μA
  • Available in (4mm × 4mm) 16-Lead QFN and 16-Pin TSSOP Packages
Designed for Automotive and Transportation Applications
AEC-Q100 generic family data available for specific packages


Typical Application

LT3517 Typical Application
LT3517 Typical Application

Description

The LT3517 is a current mode DC/DC converter with an internal 1.5A, 45V switch specifically designed to drive LEDs. The LT3517 operates as a LED driver in boost, buck mode and buck-boost mode. It combines a traditional voltage loop and a unique current loop to operate as a constant-current source or constant-voltage source. Programmable switching frequency allows optimization of the external components for efficiency or component size. The switching frequency of LT3517 can be synchronized to an external clock signal. The LED current is externally programmable with a 100mV sense resistor. The external PWM input provides up to 5000:1 LED dimming. The CTRL pin provides further 10:1 dimming ratio.

The LT3517 is available in the tiny footprint 16-lead QFN (4mm × 4mm) and the 16-pin TSSOP packages. The LT3517 provides a complete solution for both constant-voltage and constant-current applications.

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
LT3517EFE#PBF TSSOP-16 FE E 05-08-1663 (BA) Yes
LT3517EFE#TRPBF TSSOP-16 FE E 05-08-1663 (BA) Yes
LT3517EUF#PBF 4x4 QFN-16 UF E 05-08-1692 Yes
LT3517EUF#TRPBF 4x4 QFN-16 UF E 05-08-1692 Yes
LT3517HFE#PBF TSSOP-16 FE H 05-08-1663 (BA) Yes
LT3517HFE#TRPBF TSSOP-16 FE H 05-08-1663 (BA) Yes
LT3517HUF#PBF 4x4 QFN-16 UF H 05-08-1692 Yes
LT3517HUF#TRPBF 4x4 QFN-16 UF H 05-08-1692 Yes
LT3517IFE#PBF TSSOP-16 FE I 05-08-1663 (BA) Yes
LT3517IFE#TRPBF TSSOP-16 FE I 05-08-1663 (BA) Yes
LT3517IUF#PBF 4x4 QFN-16 UF I 05-08-1692 Yes
LT3517IUF#TRPBF 4x4 QFN-16 UF I 05-08-1692 Yes


LT3517 Package Drawing
LT3517 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
LT3517EFE#PBF TSSOP-16 E $4.07 $2.85 Yes
LT3517EFE#TRPBF TSSOP-16 E $2.91 Yes
LT3517EUF#PBF 4x4 QFN-16 E $3.86 $2.70 Yes
LT3517EUF#TRPBF 4x4 QFN-16 E $2.76 Yes
LT3517HFE#PBF TSSOP-16 H $5.24 $3.67 Yes
LT3517HFE#TRPBF TSSOP-16 H $3.73 Yes
LT3517HUF#PBF 4x4 QFN-16 H $4.99 $3.49 Yes
LT3517HUF#TRPBF 4x4 QFN-16 H $3.55 Yes
LT3517IFE#PBF TSSOP-16 I $4.89 $3.42 Yes
LT3517IFE#TRPBF TSSOP-16 I $3.48 Yes
LT3517IUF#PBF 4x4 QFN-16 I $4.63 $3.24 Yes
LT3517IUF#TRPBF 4x4 QFN-16 I $3.30 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
DC1279A LT3517EUF | Boost LED Driver, 3V ≤ PVIN ≤ 40V, VLED up to 40V @ 330mA $100.00
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
LT3517HFE#PBF TSSOP-16 H $5.24 $3.67 Yes
LT3517HFE#TRPBF TSSOP-16 H $3.73 Yes
LT3517HUF#PBF 4x4 QFN-16 H $4.99 $3.49 Yes
LT3517HUF#TRPBF 4x4 QFN-16 H $3.55 Yes
LT3517IFE#PBF TSSOP-16 I $4.89 $3.42 Yes
LT3517IFE#TRPBF TSSOP-16 I $3.48 Yes
LT3517IUF#PBF 4x4 QFN-16 I $4.63 $3.24 Yes
LT3517IUF#TRPBF 4x4 QFN-16 I $3.30 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

  • Display Backlighting
  • Automotive and Avionic Lighting
  • Illumination
  • Scanners

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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

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Models for the following parts are available in LTspice:
LT3517

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