TOP254PN

AC DC Converters, Offline Switchers Overview

The TOP254PN is a high-voltage integrated circuit from the TOPSwitch-II family, designed for offline flyback converters. It integrates a 700V power MOSFET with a current-mode controller, oscillator, high-voltage switched current source, thermal shutdown, and cycle-by-cycle current limiting. Operating in fixed frequency mode, it supports universal AC input voltages. The device features an internal start-up current source that draws bias current from the drain pin during startup, eliminating the need for a separate auxiliary winding initially. It offers robust protection mechanisms including over-temperature shutdown and open-loop protection.

AC DC Converters, Offline Switchers Feature Summary

• Integrates a 700V power MOSFET with advanced control logic for simplified design
• Includes built-in thermal shutdown and cycle-by-cycle current limiting for enhanced reliability
• Features an internal high-voltage switched current source for efficient startup operation

AC DC Converters, Offline Switchers Applications

• Universal AC/DC adapters for consumer electronics
• Offline flyback power supplies for battery chargers
• Standby power supplies for televisions and monitors

AC DC Converters, Offline Switchers Procurement Notes

Verify the complete part number including suffixes such as package type and tape/reel specifications against official Power Integrations documentation. Ensure compatibility with your specific PCB footprint and thermal management requirements. Confirm that the component meets all relevant safety certifications required for your target market before procurement.

AC DC Converters, Offline Switchers Selection Notes

Select this component based on the required output power level, which typically ranges up to approximately 30W depending on design efficiency and thermal constraints. Consider the operating temperature range and the need for external components like optocouplers if isolation feedback is required. Evaluate the simplicity of the fixed-frequency operation versus variable frequency alternatives for noise sensitivity.

AC DC Converters, Offline Switchers Part Context

This device belongs to the TOPSwitch-II family, representing a generation of highly integrated power switches. It succeeded earlier TOPSwitch models by offering improved efficiency and additional protection features while maintaining a compact DIP-7 or DIP-12 package option. The family is known for reducing component count in low-power offline applications.

AC DC Converters, Offline Switchers Replacement Considerations

Direct replacements within the same family include TOP252PN and TOP253PN for lower power applications. For higher power needs, consider TOP264PN. Verify pinout compatibility and thermal characteristics when substituting. Cross-referencing with other manufacturers requires careful evaluation of electrical parameters and packaging dimensions.