IC reference design search
IC manufacturers Analog Devices

IC manufacturers (103)

reference designLT3798

Analog Devices LT3798

Isolated No Opto-Coupler Flyback Controller with Active PFC

Overview

TopologyFlyback Converter
Input voltage10-38 V
Switching frequency0.5-150 kHz
Output 124 V / 2 A
Output 218 V / 0.5 A
IC revisionA

Description

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

Remarks:-Refer page 14Table 1. Predesigned Transformers-Typical Specification,Unless Otherwise Noted

Typical applications

  • High DC VIN Isolated Applications
  • Offline Bus Converter (12V, 24V or 48V Outputs)
  • Offline 5W to 100W+ Applications

More information

Products

Order Code
Data­sheet
Simu­lation
Downloads
Status
Product series
VIN
VOut1(V)
IOut1(A)
Vaux(V)
RDC 1(Ω)
RDC 2(Ω)
RDC 3(Ω)
RDC 4(Ω)
fswitch(kHz)
L(µH)
NPRI : NSEC : NAUX
ISAT(A)
VT(V (AC))
L(mm)
W(mm)
H(mm)
Mount
Size
SamplesAvailability & Sample
750811248
SPECWE-OLLT Offline Flyback Transformers, 85 - 265 V (AC), 24 V
Simu­lation
Availability
–
Downloads9 files

EDA models: Components ZIP

CAD files ZIP

Electric models ZIP

Download all 9 files as zip archive
ZIP

Status Activei| Production is active. Expected lifetime: >10 years.
Product seriesWE-OLLT Offline Flyback Transformers
Input Voltage 85 - 265 V (AC)
Output Voltage 124 V
Output Current 12 A
Auxiliary Voltage24 V
DC Resistance 10.155 Ω
DC Resistance 20.125 Ω
DC Resistance 30.025 Ω
DC Resistance 40.185 Ω
Switching Frequency 60 - 400
Inductance300 µH
Turns Ratio2:2:1:1 
Saturation Current3.5 A
Insulation Test Voltage4500 V (AC)
Length31 mm
Width31 mm
Height25 mm
MountTHT 
SizeER28/14 
–Check availability
750811330
SPECWE-OLLT Offline Flyback Transformers, 85 - 265 V (AC), 18 V
Simu­lation
Availability
–
Downloads9 files

EDA models: Components ZIP

CAD files ZIP

Electric models ZIP

Download all 9 files as zip archive
ZIP

Status Activei| Production is active. Expected lifetime: >10 years.
Product seriesWE-OLLT Offline Flyback Transformers
Input Voltage 85 - 265 V (AC)
Output Voltage 118 V
Output Current 15 A
Auxiliary Voltage18 V
DC Resistance 10.15 Ω
DC Resistance 20.008 Ω
DC Resistance 30.042 Ω
–
Switching Frequency 200
Inductance300 µH
Turns Ratio6:1:1 
Saturation Current4 A
Insulation Test Voltage4500 V (AC)
Length39.6 mm
Width43.18 mm
Height30.48 mm
MountTHT 
SizeETD34 
–Check availability