The LT3799EMSE is an isolated flyback controller with power factor correction specifically designed for driving LEDs. The controller operates using critical conduction mode allowing the use of a small transformer. Using a novel current sensing scheme, the controller is able to deliver a well regulated current to the secondary side without using an opto-coupler. A strong gate driver is included to drive an external high voltage MOSFET. Utilizing an onboard multiplier, the LT3799EMSE typically achieves power factors of 0.97. The FAULT pin provides notification of open and short LED conditions.
The LT3799EMSE uses a micropower hysteretic start-up to efficiently operate at offline input voltages, with a third winding to provide power to the part. An internal LDO provides a well regulated supply for the part’s internal circuitry and gate driver.
TRIAC DimmableLED Current RegulationLT3799YES±10%LT3799-1NO±5%Feature
- Isolated PFC LED Driver with Minimum Number of External Components
- TRIAC Dimmable
- VIN and VOUT Limited Only by External Components
- Active Power Factor Correction (Typical PFC > 0.97)
- Low Harmonic Content
- No Opto-Coupler Required
- Accurate Regulated LED Current (±5% Typical)
- Open LED and Shorted LED Protection
- Thermally Enhanced 16-lead MSOP Package
Applications
- Offline 4W to 100W+ LED Applications
- High DC VIN LED Applications
(Picture: Pinout)
