LinkSwitch™-TN2 highly energy efficient off-line switcher IC with integrated system level protection for low component-count power supplies of ICs for non-isolated off-line power supplies provides dramatically improved performance compared to traditional linear or cap-dropper solutions. Designs using the highly integrated LinkSwitch-TN2 ICs are more flexible and feature increased efficiency, comprehensive system level protection and higher reliability. This family supports buck, buck-boost and flyback converter topologies. Each device incorporates power MOSFET, oscillator, on/off control for highest efficiency at light load, high-voltage switched current source for self-biasing, frequency jittering, fast (cycle-by-cycle) current limit, hysteretic thermal shutdown, output and input overvoltage protection circuitry onto a monolithic IC. Applications includes appliances, metering, smart LED drivers, industrial controls, IOT, home and building automation.