LT3518 - Full-Featured LED Driver with 2.3A Switch Current


  • 3000:1 True Color PWM™ Dimming Ratio
  • 2.3A, 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

Typical Application

LT3518 Typical Application
LT3518 Typical Application


The LT3518 is a current mode DC/DC converter with an internal 2.3A, 45V switch specifically designed to drive LEDs. The LT3518 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 the LT3518 can be synchronized to an external clock signal. The LED current is externally programmable with a 100mV sense resistor. The external PWM input provides 3000:1 LED dimming. The CTRL pin provides further 10:1 dimming ratio.

The LT3518 is available in the tiny footprint 16-lead QFN (4mm × 4mm) and the 16-pin TSSOP package. The LT3518 provides a complete solution for both constant-voltage and constant-current applications.


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

Part Number Package Code Temp Package
LT3518EFE TSSOP-16 FE E 05-08-1663 (BA) RoHS
LT3518EFE#PBF TSSOP-16 FE E 05-08-1663 (BA) RoHS
LT3518EFE#TRPBF TSSOP-16 FE E 05-08-1663 (BA) RoHS
LT3518EUF#PBF 4x4 QFN-16 UF E 05-08-1692 RoHS
LT3518EUF#TRPBF 4x4 QFN-16 UF E 05-08-1692 RoHS
LT3518HFE TSSOP-16 FE H 05-08-1663 (BA) RoHS
LT3518HFE#PBF TSSOP-16 FE H 05-08-1663 (BA) RoHS
LT3518HFE#TRPBF TSSOP-16 FE H 05-08-1663 (BA) RoHS
LT3518HUF#PBF 4x4 QFN-16 UF H 05-08-1692 RoHS
LT3518HUF#TRPBF 4x4 QFN-16 UF H 05-08-1692 RoHS
LT3518IFE TSSOP-16 FE I 05-08-1663 (BA) RoHS
LT3518IFE#PBF TSSOP-16 FE I 05-08-1663 (BA) RoHS
LT3518IFE#TRPBF TSSOP-16 FE I 05-08-1663 (BA) RoHS
LT3518IUF#PBF 4x4 QFN-16 UF I 05-08-1692 RoHS
LT3518IUF#TRPBF 4x4 QFN-16 UF I 05-08-1692 RoHS

LT3518 Package Drawing
LT3518 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
LT3518EFE TSSOP-16 E $8.86 $6.20 No
LT3518EFE#PBF TSSOP-16 E $4.43 $3.10 Yes
LT3518EFE#TRPBF TSSOP-16 E $3.16 Yes
LT3518EUF#PBF 4x4 QFN-16 E $4.21 $2.95 Yes
LT3518EUF#TRPBF 4x4 QFN-16 E $3.01 Yes
LT3518HFE TSSOP-16 H $11.34 $7.94 No
LT3518HFE#PBF TSSOP-16 H $5.67 $3.97 Yes
LT3518HFE#TRPBF TSSOP-16 H $4.03 Yes
LT3518HUF#PBF 4x4 QFN-16 H $5.42 $3.79 Yes
LT3518HUF#TRPBF 4x4 QFN-16 H $3.85 Yes
LT3518IFE TSSOP-16 I $10.62 $7.44 No
LT3518IFE#PBF TSSOP-16 I $5.31 $3.72 Yes
LT3518IFE#TRPBF TSSOP-16 I $3.78 Yes
LT3518IUF#PBF 4x4 QFN-16 I $5.06 $3.54 Yes
LT3518IUF#TRPBF 4x4 QFN-16 I $3.60 Yes
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* 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
DC1160A LT3518EUF Demo Board $100.00
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