LTC3783 - PWM LED Driver and Boost, Flyback and SEPIC Converter

Features

  • True Color PWM Delivers Constant Color with 3000:1 Dimming Ratio
  • Fully Integrated Load FET Driver for PWM Dimming Control of High Power LEDs
  • 100:1 Dimming from Analog Inputs
  • Wide FB Voltage Range: 0V to 1.23V
  • Constant Current or Constant Voltage Regulation
  • Low Shutdown Current: IQ = 20μA
  • 1% 1.23V Internal Voltage Reference
  • 2% RUN Pin Threshold with 100mV Hysteresis
  • Programmable Operating Frequency (20kHz to  1MHz) with One External Resistor
  • Synchronizable to an External Clock Up to 1.3fOSC
  • Internal 7V Low Dropout Voltage Regulator
  • Programmable Output Overvoltage Protection
  • Programmable Soft-Start
  • Can be Used in a No RSENSE Mode for VDS < 36V
  • 16-Lead DFN and TSSOP Packages

Typical Application

LTC3783 Typical Application
LTC3783 Typical Application

Description

The LTC3783 is a current mode LED driver and boost, flyback and SEPIC controller that drives both an N-channel power MOSFET and an N-channel load PWM switch. When using an external load switch, the PWMIN input not only drives PWMOUT, but also enables controller GATE switching and error amplifier operation, allowing the controller to store load current information while PWMIN is low. This feature (patent pending) provides extremely fast, true PWM load switching with no transient overvoltage or undervoltage issues; LED dimming ratios of 3000:1 can be achieved digitally, avoiding the color shift normally associated with LED current dimming. The FBP pin allows analog dimming of load current, further increasing the effective dimming ratio by 100:1 over PWM alone.

In applications where output load current must be returned to VIN, optional constant current/constant voltage regulation controls either output (or input) current or output voltage and provides a limit for the other. ILIM provides a 10:1 analog dimming ratio.

For low- to medium-power applications, No RSENSE mode can utilize the power MOSFET’s on-resistance to eliminate the current-sense resistor, thereby maximizing efficiency. The IC’s operating frequency can be set with an external resistor over a 20kHz to 1MHz range and can be synchronized to an external clock using the SYNC pin.

The LTC3783 is available in the 16-lead DFN and TSSOP packages.

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
LTC3783EDHD#PBF 5x4 DFN-16 DHD E 05-08-1707 Yes
LTC3783EDHD#TRPBF 5x4 DFN-16 DHD E 05-08-1707 Yes
LTC3783EFE#PBF TSSOP-16 FE E 05-08-1663 (BC) Yes
LTC3783EFE#TRPBF TSSOP-16 FE E 05-08-1663 (BC) Yes
LTC3783IDHD#PBF 5x4 DFN-16 DHD I 05-08-1707 Yes
LTC3783IDHD#TRPBF 5x4 DFN-16 DHD I 05-08-1707 Yes
LTC3783IFE#PBF TSSOP-16 FE I 05-08-1663 (BC) Yes
LTC3783IFE#TRPBF TSSOP-16 FE I 05-08-1663 (BC) Yes


LTC3783 Package Drawing
LTC3783 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
LTC3783EDHD#PBF 5x4 DFN-16 E $4.07 $2.85 Yes
LTC3783EDHD#TRPBF 5x4 DFN-16 E $2.91 Yes
LTC3783EFE#PBF TSSOP-16 E $4.07 $2.85 Yes
LTC3783EFE#TRPBF TSSOP-16 E $2.97 Yes
LTC3783IDHD#PBF 5x4 DFN-16 I $4.29 $3.00 Yes
LTC3783IDHD#TRPBF 5x4 DFN-16 I $3.06 Yes
LTC3783IFE#PBF TSSOP-16 I $4.29 $3.00 Yes
LTC3783IFE#TRPBF TSSOP-16 I $3.06 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
DC850A LTC3783 Demo Board | Boost LED Driver Controller, 3V ≤ VIN ≤ 14.4V, VLED up to 25V @ 360mA $125.00
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Click here to view our complete list of demo boards

Applications

  • High Voltage LED Arrays
  • Telecom Power Supplies
  • 42V Automotive Systems
  • 24V Industrial Controls
  • IP Phone Power Supplies

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Design Tools

LTspice

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LTC3783

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