560V Micropower No-Opto Isolated Flyback Converter with 630V/300mA Switch

The LT8315 is a high voltage flyback converter with integrated 630V/300mA switch. No opto-isolator is needed for regulation. The device samples the output voltage from the isolated flyback waveform appearing across a third winding on the transformer. Quasi-resonant boundary mode operation improves load regulation, reduces transformer size, and maintains high efficiency.

At start-up, the LT8315 charges its INTVCC capacitor via a current source attached to the DRAIN pin. During normal operation, the current source turns off and the device draws its power from a third winding on the transformer.

The LT8315 operates from a wide range of input supply voltages and can deliver up to 15W of power. It is available in a thermally enhanced 20-pin TSSOP package with four pins removed for high-voltage spacing.

Applications

* Isolated Telecom, Automotive, Industrial, Medical Power Supplies

* Isolated Off Line Housekeeping Power Supplies

* Electric Vehicles and Battery Stacks

* Wide Input Voltage Range: 18V to 560V

* 630V/300mA Integrated Power Switch

* No Opto-Isolator Required for Regulation

* Quasi-Resonant Boundary Mode Operation

* Constant-Current and Constant-Voltage Regulation

* Low-Ripple Light Load Burst Mode® Operation

* Low Quiescent Current: 70μA

* Programmable Current Limit and Soft-Start

* TSSOP Package with High Voltage Spacing