nn 5V to 100V Input Voltage Range
nn 1.9A Average Gate Drive Source and Sink Current
nn Boundary Mode Operation
nn No Transformer Third Winding or Opto-Isolator
Required for Regulation
nn Primary-Side Winding Feedback Load Regulation
nn VOUT Set with Two External Resistors
nn INTVCC Pin for Control of Gate Driver Voltage
nn Programmable Soft Start
nn Programmable Undervoltage Lockout
nn Available in MSOP Package
nn Isolated Telecom Converters
nn High Power Automotive Supplies
nn Isolated Industrial Power Supplies
nn Military and High Temperature Applications
The LT®3748 is a switching regulator controller specifically
designed for the isolated flyback topology and capable of
high power. It drives a low side external N-channel power
MOSFET from an internally regulated 7V supply. No third
winding or opto-isolator is required for regulation as the
part senses the isolated output voltage directly from the
primary-side flyback waveform.
The LT3748 utilizes boundary mode to provide a small
magnetic solution without compromising load regulation.
Operating frequency is set by load current and transformer
magnetizing inductance. The gate drive of the LT3748
combined with a suitable external MOSFET allow it to
deliver load power up to several tens of watts from input
voltages as high as 100V.
The LT3748 is available in a high voltage 16-lead MSOP
package with four leads removed.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Protected by U.S. Patents, including 5438499 and 7471522.
25W, 12V Output, Isolated Telecom Supply
36V TO 72V
VC GND INTVCC
Output Load and Line Regulation
VIN = 72V
VIN = 48V
VIN = 36V
0.5 1.0 1.5
LOAD CURRENT (A)
For more information www.linear.com/LT3748