LT3798 - Isolated No Opto-Coupler Flyback Controller with Active PFC

The LT®3798 is a constant-voltage/constant-current isolated flyback controller that combines active power factor correction (PFC) with no opto-coupler required for output voltage feedback into a single-stage converter. A LT3798 based design can achieve a power factor of greater than 0.97 by actively modulating the input current, allowing compliance with most Harmonic Current Emission requirements.

The LT3798 is well suited for a wide variety of off-line applications. The input range can be scaled up or down, depending mainly on the choice of external components. Efficiencies higher than 86% can be achieved with output power levels up to 100W. In addition, the LT3798 can easily be designed into high DC input applications.

Features
  • Isolated PFC Flyback with Minimum Number of External Components
  • VIN and VOUT Limited Only by External Components
  • Active Power Factor Correction
  • Low Harmonic Distortion
  • No Opto-Coupler Required
  • Constant-Current and Constant-Voltage Regulation
  • Accurate Regulated Voltage and Current (±5% Typical)
  • Energy Star Compliant (<0.5W No Load Operation)
  • Thermally Enhanced 16-lead MSOP Package
Typical Application
LT3798 Typical Application
LT3798 Typical Application
Applications
  • Offline 5W to 100W+ Applications
  • High DC VIN Isolated Applications
  • Offline Bus Converter (12V, 24V or 48V Outputs)
Packaging
LT3798 Package Drawing
Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
LT3798EMSE#PBFMS-16EE$3.22$2.25
LT3798EMSE#TRPBFMS-16EE$2.31
LT3798HMSE#PBFMS-16EH$4.11$2.88
LT3798HMSE#TRPBFMS-16EH$2.94
LT3798IMSE#PBFMS-16EI$3.70$2.59
LT3798IMSE#TRPBFMS-16EI$2.65
LT3798MPMSE#PBFMS-16EMP$9.99$6.99
LT3798MPMSE#TRPBFMS-16EMP$7.05
Demo Boards
Part NumberDescriptionPrice
DC1817BLT3798EMSE Isolated Demo Board VIN = 90VAC to 265VAC, VOUT = 24V @ 2A High Voltage$200.00
Datasheet
Reliability Data
Product Selector Card
Press Release
CAD Symbol
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