DESCRIPTION
The LT®3574 is a monolithic switching regulator specifically designed for the isolated flyback topology. No third winding or opto-isolator is required for regulation. The part senses the isolated output voltage directly from the primary side flyback waveform. A 0.65A, 60V NPN power switch is integrated along with all control logic into a 16-lead MSOP package.

FEATUREs
■ 3V to 40V Input Voltage Range
■ 0.65A, 60V Integrated NPN Power Switch
■ Boundary Mode Operation
■ No Transformer Third Winding or Opto-Isolator 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
■ 16-Lead MSOP Package

APPLICATIONS
■ Industrial, Automotive and Medical Isolated Power Supplies