Power Integrations

TOP242P

TOP242P Description

The TOP242P from Power Integrations is an obsolete but historically significant offline switcher IC designed for flyback topology applications. Packaged in an 8DIP through-hole format, it integrates a 700V breakdown voltage MOSFET, enabling robust performance in AC/DC power conversion systems. With a 15W power rating, it supports isolated outputs and operates at a switching frequency range of 66kHz to 132kHz, adjustable via frequency control. Its 66.5% duty cycle and integrated protections—including current limiting, over-temperature, and over-voltage shutdown—make it a reliable choice for constrained designs.

TOP242P Features

• Integrated 700V MOSFET: Reduces external component count for compact designs.
• Frequency Control: Adjustable 66kHz–132kHz range for optimized efficiency.
• Comprehensive Protections: Built-in current limiting, over-temperature, and over-voltage fault protection.
• High Duty Cycle: 66.5% maximizes power delivery in discontinuous conduction mode (DCM).
• Isolated Output: Ensures safety in offline power supplies.
• Wide Input Compatibility: Suitable for universal mains applications (85VAC–265VAC).

TOP242P Applications

Ideal for low-to-mid-power offline SMPS designs, the TOP242P excels in:

• Auxiliary power supplies for industrial equipment.
• Consumer electronics (e.g., set-top boxes, LED drivers).
• Embedded systems requiring compact, isolated power.
• Legacy designs where through-hole mounting is preferred.

Conclusion of TOP242P

While obsolete, the TOP242P remains a benchmark for integrated offline switchers, offering a balance of simplicity, protection, and efficiency. Its flyback topology and all-in-one design reduce BOM costs, making it a pragmatic choice for 15W applications. Engineers maintaining legacy systems or seeking proven reliability may still find value in its architecture. For newer designs, consider Power Integrations' modern alternatives with enhanced features.