UC2855ADWTR

Overview

The UC2855ADWTR is a high-performance power factor correction controller manufactured by Texas Instruments. It operates within a supply voltage range of 10 V to 20 V and supports switching frequencies up to 500 kHz. The device features an integrated soft-start circuit, adjustable current limit threshold, and zero-power detection for efficient operation. Designed for surface-mount applications, it is housed in a 20-pin SOIC package. The component functions as a pre-regulator with advanced control characteristics including frequency control, ramp compensation, and current limiting to ensure stable power factor correction.

Feature Summary

• Integrated zero-power detection capability for enhanced efficiency at low loads
• Built-in soft-start mechanism to minimize inrush current during startup
• Adjustable current limit threshold allowing flexible design configurations
• Supports multiple PFC topologies including boost and buck-boost architectures

Applications

• High-performance power factor correction pre-regulators
• Universal AC-DC power supplies
• Industrial power management systems
• Consumer electronics requiring compliant power input

Procurement Notes

Verify the specific suffix 'DWTR' corresponds to the tape-and-reel packaging format required for automated assembly processes. Confirm that the operating temperature range aligns with the intended environmental conditions, as industrial variants may differ from commercial equivalents. Ensure compatibility with the selected PCB footprint for the 20-SOIC package before finalizing procurement orders.

Selection Notes

Select this component when designing systems requiring active power factor correction with integrated soft-start and zero-power detection features. Consider the 500 kHz maximum switching frequency for balancing component size and efficiency. Evaluate the 20-V maximum supply voltage against the system's auxiliary power requirements. Compare against other UC285x series devices if different pinouts or specific topology constraints are necessary for the application.

Part Context

The UC2855ADWTR belongs to the UC2855 family of power factor correction controllers from Texas Instruments. This series is designed to meet regulatory standards for harmonic distortion in AC power inputs. The ADWTR designation indicates the automotive-grade or extended temperature variant packaged in reels, distinguishing it from tube-packaged versions like the UC2855BDW.

Replacement Considerations

Direct substitutes include the UC2855BDW for tube packaging or the UC2854 series for similar functionality with different switching frequency limits. Verify pin-to-pin compatibility and electrical parameter overlaps before swapping components in existing designs.