STACF01A

AC DC Converters, Offline Switchers Overview

The STACF01A is an active clamp flyback controller IC designed for high-performance AC-DC adapters using GaN HEMTs, supporting power ratings up to 100W and beyond. It features non-complementary driving of the high-side switch and operates at frequencies up to 500kHz with programmable deadtime. The device employs multimode operation including variable frequency with foldback, bottom-clamped proportional frequency, and burst mode to optimize efficiency across wide load ranges. An automatic adjustment mechanism ensures proper reverse primary current for ZVS under any input/output voltage combination.

AC DC Converters, Offline Switchers Feature Summary

• Non-complementary control of active clamp flyback converter
• Multimode operation optimizes efficiency over a very wide load range
• Automatic reverse current control for ZVS of low-side switch
• Embedded high-voltage startup and active X-cap discharge circuit

AC DC Converters, Offline Switchers Applications

• High power density USB PD chargers based on GaN HEMTs
• High power density USB PD adapters based on GaN HEMTs

AC DC Converters, Offline Switchers Procurement Notes

Verify the specific suffix against official documentation to confirm AC input compatibility, as the 'A' variant includes X-capacitor discharge functionality not present in the DC-input 'B' version. Ensure the ordering code matches the required package and tape-and-reel specifications provided in the manufacturer's datasheet to avoid integration errors.

AC DC Converters, Offline Switchers Selection Notes

Select this component for designs requiring seamless mode transitions between heavy-medium loads and no-load conditions to maximize energy efficiency. It is specifically intended for use with external GaN power ICs or half-bridge drivers, offering dual low-side drivers for easy pairing with MasterGaN series devices. Consider the integrated buck-boost regulator for wide output voltage range requirements.

AC DC Converters, Offline Switchers Part Context

This IC belongs to STMicroelectronics' family of active clamp flyback controllers tailored for modern high-density power supplies. It complements other GaN-focused solutions by providing precise timing control and protection features necessary for reliable operation in compact AC-DC adapter form factors targeting USB Power Delivery standards.

AC DC Converters, Offline Switchers Replacement Considerations

The STACF01B serves as a functional alternative for DC-input applications, lacking the X-capacitor discharge feature found in the STACF01A. Verify input source type before substitution to ensure compliance with safety regulations regarding line voltage monitoring and capacitor discharge.