Power Integrations

TOP223P

TOP223P Description

The TOP223P from Power Integrations is an obsolete but historically significant offline switching IC designed for AC/DC power conversion applications. Housed in an 8-pin DIP through-hole package, it integrates a 700V breakdown voltage MOSFET, enabling robust performance in isolated power supplies. With a 100kHz switching frequency and 25W power handling, it supports topologies like Boost, Buck, Flyback, and Forward, making it versatile for diverse designs. Its 67% duty cycle and built-in protections (current limiting, over-temperature) enhance reliability in demanding environments. Although no longer in production, it remains a reference for compact, high-voltage offline converters.

TOP223P Features

• Integrated 700V MOSFET: Eliminates external switches, reducing BOM complexity.
• Multi-Topology Support: Compatible with Boost, Buck, Flyback, and Forward configurations.
• Protection Mechanisms: Built-in current limiting and thermal shutdown for fault resilience.
• High Switching Frequency (100kHz): Enables smaller magnetics and capacitors for compact designs.
• Isolated Output: Suitable for safety-critical applications requiring galvanic isolation.
• Wide Duty Cycle (67%): Optimizes efficiency across varying load conditions.

TOP223P Applications

Ideal for low-to-mid-power offline SMPS designs, the TOP223P excels in:

• Industrial Power Supplies: Reliable operation in harsh environments.
• Consumer Electronics: Compact adapters for set-top boxes, routers, or LED drivers.
• Auxiliary Power Modules: Isolated bias supplies for motor drives or inverters.
• Legacy Equipment Repairs: Replacement for obsolete systems originally using this IC.

Conclusion of TOP223P

While superseded by newer technologies, the TOP223P set a benchmark for integrated offline switchers, combining high voltage tolerance, topology flexibility, and robust protection. Its legacy persists in designs prioritizing simplicity and isolation, though modern alternatives offer improved efficiency and smaller footprints. Engineers evaluating legacy systems or educational projects may still find its specifications instructive.