ML4812IQ

Overview

The ML4812IQ is a fixed-frequency current-mode PWM controller designed for power factor correction (PFC) applications. It operates with an internal oscillator set to a switching frequency of 76 kHz. The device integrates a high-voltage startup circuit, allowing operation from supply voltages up to 30 V during start-up and down to 10 V during normal operation. It features a precision multiplier for sinusoidal line current shaping and includes comprehensive protection mechanisms such as overvoltage lockout, undervoltage lockout, and thermal shutdown.

Feature Summary

• Integrates a high-voltage startup circuit for simplified biasing
• Provides fixed-frequency current-mode control for stable regulation
• Includes built-in thermal shutdown for enhanced reliability

Applications

• Power factor correction in AC-DC converters
• Universal input power supplies
• Industrial power systems

Procurement Notes

Verify the specific suffix 'IQ' against the manufacturer's official datasheet to confirm package type and temperature range. Ensure compatibility with existing PCB footprints and thermal management requirements before procurement.

Selection Notes

Select this component for designs requiring a dedicated PFC controller with integrated startup capabilities. Consider the fixed 76 kHz frequency when designing magnetic components. Verify that the operating voltage range aligns with the system's rail specifications.

Part Context

This part belongs to onsemi's legacy PFC controller portfolio, often associated with the L4824 series. It is designed for standalone PFC stages in offline power conversion applications, providing essential control functions for improving power quality in electronic loads.

Replacement Considerations

The ML4824 series may serve as a functional alternative. Confirm pinout compatibility and electrical parameter equivalence through official cross-reference documentation before substitution.