LT1737

LT1737 High Power Isolated Flyback Controller FEATURES s s s DESCRIPTIO s s s s s s s s s Drives External Power MOSFET Supply Voltage Range: 4.5V to 20V Flyback Voltage Limited Only by External Components Senses Output Voltage Directly from Primary Side Winding—No Optoisolator Required Switching Frequency from 50kHz to 250kHz with External Capacitor Moderate Accuracy Regulation Without User Trims Regulation Maintained Well into Discontinuous Mode External ISENSE Resistor Optional Load Compensation Optional Undervoltage Lockout Shutdown Feature Reduces IQ to 50µA Typ Available in 16-Pin GN and SO Packages The LT®1737 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 (see Applications Information). Its gate drive capability, coupled with a suitable external MOSFET and other power path components, can deliver load power up to tens of Watts. The LT1737 has a number of features not found on other isolated flyback controller ICs. 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 fo...