42V Micropower No-Opto Isolated Flyback Converter with 65V/3.6A Switch

The LT8302/LT8302-3 is a monolithic micropower isolated flyback converter. By sampling the isolated output voltage directly from the primary-side flyback waveform, the part requires no third winding or opto-isolator for regulation. The output voltage is programmed with two external resistors and a third optional temperature compensation resistor. Boundary mode operation provides a small magnetic solution with excellent load regulation. Low ripple Burst Mode operation maintains high efficiency at light load while minimizing the output voltage ripple. A 3.6A, 65V DMOS power switch is integrated along with all the high voltage circuitry and control logic into a thermally enhanced 8-lead SO package.

The LT8302/LT8302-3 operates from an input voltage range of 3V to 42V and delivers up to 18W of isolated output power. The high level of integration and the use of boundary and low ripple burst modes result in a simple to use, low component count, and high efficiency application solution for isolated power delivery.

Applications

* Isolated Automotive, Industrial, Medical Power Supplies

* Isolated Auxiliary/Housekeeping Power Supplies

* 3V to 42V Input Voltage Range

* 3.6A, 65V Internal DMOS Power Switch

* Low Quiescent Current:

* 106µA in Sleep Mode

* 380µA in Active Mode

* Quasi-Resonant Boundary Mode Operation at Heavy Load

* Low Ripple Burst Mode® Operation at Light Load

* Minimum Load < 0.5% (Typ) of Full Output