Overview
Features and Benefits
- PWM Dimming Provides Up to 3000:1 Dimming Ratio
- CTRL_SEL Dimming Provides Up to 3000:1 Dimming Ratio Between Any Current
- Three-State Current Control for Color Mixing
- ±6% Current Regulation Accuracy
- 6V to 36V Input Voltage Range
- Average Current Mode Control
- 2μs Maximum Recovery Time Between Any Current Regulation State
- <1μA Shutdown Current
- Output Voltage Regulation and Open-LED Protection
- Thermally Enhanced 4mm × 5mm QFN and 28-Pin FE Package
Product Details
The LT3743 is a fixed frequency synchronous step-down DC/DC controller designed to drive high current LEDs. The average current mode controller will maintain inductor current regulation over a wide output voltage range of 0V to (VIN – 2V). LED dimming is achieved through analog dimming on the CTRL_L, CTRL_H and CTRL_T pins and with PWM dimming on the PWM and CTRL_SEL pins. Through the use of externally switched load capacitors, the LT3743 is capable of changing regulated LED current levels within several μs, providing accurate, high speed PWM dimming between two current levels. The switching frequency is programmable from 200kHz to 1MHz through an external resistor on the RT pin.
Additional features include voltage regulation and overvoltage protection set with a voltage divider from the output to the FB pin. Overcurrent protection is provided and set by the CTRL_H pin.
Applications
- DLP Projectors
- High Power Architectural Lighting
- Laser Diodes
Product Categories
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation
Reliability Data (1)
User Guides (1)
Tools & Simulations
LTspice
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Models for the following parts are available in LTspice:
Reference Materials
Press Releases (1)
Technical Articles (1)
Design Resources
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PCN-PDN Information
Support & Discussions
LT3743 Discussions
Sample & Buy
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 Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.
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Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.