IC manufacturers Analog Devices

IC manufacturers (103)

Analog Devices LT3575

Isolated Flyback Converter without an Opto-Coupler

Overview

TopologyFlyback Converter
Input voltage3-40 V
Output 112 V / 1 A
Output 224 V / 0.5 A

Description

The LT3575 is a monolithic switching regulator specifically designed for the isolated flyback topology. No third winding or optoisolator is required for regulation. The part senses the isolated output voltage directly from the primary side flyback waveform. A 2.5A, 60V NPN power switch is integrated along with all control logic into a 16-lead TSSOP package.

The LT3575 operates with input supply voltages from 3V to 40V, and can deliver output power up to 14W with no external power switch.The LT3575 utilizes boundary mode operation to provide a small magnetic solution with improved load regulation.

The output voltage is easily set with two external resistors and the transformer turns ratio. Off the shelf transformers are available for many applications.

Features

  • 3V to 40V Input Voltage Range
  • 2.5A, 60V Integrated NPN Power Switch
  • Boundary Mode Operation
  • No Transformer Third Winding orOptoisolator Required for Regulation
  • Improved Primary-Side Winding Feedback Load Regulation
  • VOUT Set with Two External Resistors
  • BIAS Pin for Internal Bias Supply and Power NPN Driver
  • Programmable Soft-Start
  • Programmable Power Switch Current Limit
  • Thermally Enhanced 16-Lead TSSOP

Remarks:

  • See page num 11 for more inductor values.

Typical applications

  • Medical Isolated Power Supplies
  • Automotive
  • Industrial

Products

Order Code
Data­sheet
Simu­lation
Downloads
Status
Product series
VIN
VOut1(V)
IOut1(A)
Vaux(V)
L(µH)
n
ISAT(A)
LS(µH)
VT(V (AC))
Size
IC Reference
Samples
WE-FB Flyback Transformer suitable for LT3573/ LT3574/ LT3575/ LT3748, 9 - 36 V (DC), 12 V
Simu­lation
Status Activei| Production is active. Expected lifetime: >10 years.
Input Voltage 9 - 36 V (DC)
Output Voltage 112 V
Output Current 11 A
Auxiliary Voltage8 V
Inductance100 µH
Turns Ratio3:1:0.667 
Saturation Current1.65 A
Leakage Inductance3 µH
Insulation Test Voltage1500 V (AC)
SizeEP10 
IC ReferenceLT3575 
WE-FB Flyback Transformer suitable for LT3573/ LT3574/ LT3575/ LT3748, 9 - 36 V (DC), 24 V
Simu­lation
Status Activei| Production is active. Expected lifetime: >10 years.
Input Voltage 9 - 36 V (DC)
Output Voltage 124 V
Output Current 10.5 A
Auxiliary Voltage8 V
Inductance100 µH
Turns Ratio1:1:0.333 
Saturation Current2.1 A
Leakage Inductance3 µH
Insulation Test Voltage1500 V (AC)
SizeEP10 
IC ReferenceLT3574 & LT3575 
WE-FB Flyback Transformer suitable for LT3573/ LT3574/ LT3575/ LT3748, 36 V (DC), 24 V
Simu­lation
Status Activei| Production is active. Expected lifetime: >10 years.
Input Voltage 36 V (DC)
Output Voltage 124 V
Output Current 10.5 A
Auxiliary Voltage8 V
Inductance100 µH
Turns Ratio2:1:0.33 
Saturation Current1.9 A
Leakage Inductance3 µH
Insulation Test Voltage1500 V (AC)
SizeEP10 
IC ReferenceLT3574 & LT3575