MC34262DG

Overview

The MC34262DG is a Critical Conduction Mode (CRM) Power Factor Controller manufactured by onsemi, designed for pre-converters in electronic ballasts and offline power supplies. It operates within a supply voltage range of 12V to 28V and supports switching frequencies up to 50 kHz. The device functions across an operating temperature range of 0°C to +85°C and utilizes an 8-SOIC surface-mount package with a width of 3.90mm. Key electrical characteristics include a startup current of 250 µA and a maximum source/sink current capability of 200 mA.

Feature Summary

• Features a single-quadrant dual-input multiplier that maintains linear transmission curves to reduce line current distortion.
• Incorporates a zero-current detector that triggers the next conduction period when inductor current reaches zero.
• Includes a transconductance error amplifier with stable gain characteristics across varying temperatures.
• Provides comprehensive protection mechanisms including overvoltage comparison, undervoltage lockout, and per-cycle current limiting.

Applications

• Active power factor correction in electronic ballasts
• Pre-converter stages for offline power supplies
• Flyback converter topologies requiring CRM operation

Procurement Notes

Verify component authenticity through authorized distributors as the part is obsolete. Confirm RoHS compliance status, as original specifications may differ from current manufacturing standards. Check for available alternatives like the L6561D if new production is required. Ensure the 8-SOIC package matches your PCB footprint requirements before finalizing procurement decisions.

Selection Notes

Select this controller for applications requiring critical conduction mode efficiency without complex control loops. The integrated zero-current detection simplifies design by reducing reverse recovery losses in output rectifiers. Consider the 8-SOIC package constraints for thermal management and board space. Evaluate the 12V to 28V supply range against your system's input voltage stability.

Part Context

This component belongs to the MC34262/MC33262 family of power factor controllers. It shares functional similarities with other CRM controllers but is distinct in its specific internal architecture featuring a fast-start circuit and图腾柱 output stage. The DG suffix denotes the SOIC surface-mount variant, differentiating it from the PDIP through-hole version.

Replacement Considerations

Public confirmed substitute part numbers include L6561D and L6561D013TR from STMicroelectronics. These devices offer similar CRM functionality and pin compatibility for direct replacement in existing designs.

FAQ

How does the zero-current detector improve efficiency?

It ensures the MOSFET turns on only when inductor current reaches zero, minimizing switching losses and allowing the use of lower-cost rectifiers with slower reverse recovery times.

What is the purpose of the fast-start circuit?

The fast-start circuit pre-charges the compensation capacitor during initial startup, allowing the driver output to switch immediately and reducing start-up delay.