TOP224YN is a switch-mode power supply (SMPS) controller IC made by Power Integrations. It belongs to the TOPSwitch-II family, designed for converting AC mains voltage into regulated DC power in power supplies. 

It integrates several circuits inside one chip, including a high-voltage MOSFET, PWM controller, and protection circuits, which allows power supplies to work with fewer external components. 

Main Specifications

• Type: Offline PWM switch (AC-DC converter)

• Series: TOPSwitch-II

• Input voltage: 85–265 VAC

• Maximum output power: about 45 W (wide input) or 75 W (single voltage input) 

• Switching frequency: about 100 kHz 

• Breakdown voltage: 700 V 

• Package: TO-220-3

• Operating temperature: −40 °C to +150 °C