The LT1737CS#PBF is a monolithic Switching Regulator Controller specifically designed for the isolated flyback topology. It drives the gate of an external MOSFET and is generally powered from a DC supply voltage. Output voltage feedback information may be supplied by a variety of methods including a third transformer winding, the primary winding or even direct DC feedback. Its gate drive capability coupled with a suitable external MOSFET and other power path components can deliver load power up to tens of Watts. It has a number of features not found on other isolated flyback controller ICs presently available. By utilizing current-mode switching techniques, it provides excellent AC and DC line regulation. Its unique control circuitry can maintain regulation well into discontinuous mode in most applications. Optional load compensation circuitry allows for improved load regulation. An optional undervoltage lockout pin halts operation when the application input voltage is too low.
Drives external power MOSFET
Flyback voltage limited only by external components
Senses output voltage directly from primary side winding - no optoisolator required
Moderate accuracy regulation without user trims
Regulation maintained well into discontinuous mode
(EN)
