TinySwitch-III AC/DC Off-Line Switcher IC, 18W, DIP-7

The TinySwitch-III AC/DC Off-Line Switcher IC from Power Integrations represents a pinnacle of energy-efficient power supply design. This highly integrated circuit combines a robust 700V power MOSFET, oscillator, high-voltage switched current source, and comprehensive protection features including user-selectable current limit and accurate hysteretic thermal shutdown with automatic recovery. Employing a simple ON/OFF control scheme, it eliminates the need for complex loop compensation, enabling a very low component count that enhances overall system reliability and facilitates cost-effective, single-sided printed circuit board layouts.

Engineered for exceptional performance, the TinySwitch-III family delivers a high bandwidth for fast turn-on with no overshoot and excellent transient load response. Its advanced EcoSmart™ technology ensures extremely high energy efficiency, easily meeting stringent global regulations such as mandatory CEC and the 1W PC standby requirement. The device maintains constant efficiency even under very light loads, with a remarkably low no-load consumption of less than 150mW at 265V AC.

Key reliability features include improved auto-restart, which limits power delivery to less than 3% of maximum during fault conditions like short-circuit or open loop, and tight I2f parameter tolerance for reduced system cost. The self-biased design requires no auxiliary bias winding or components, while integrated frequency jittering lowers EMI filter costs. The thoughtful pin-out simplifies heat sinking directly to the PCB, and the electrically quiet SOURCE pins contribute to lower electromagnetic interference.

This IC is an ideal, flexible solution for creating compact, reliable, and cost-effective switched-mode power supplies across a vast range of consumer and industrial applications.