UC2871DW

Overview

The UC2871DW is a quasi-resonant flyback controller manufactured by Texas Instruments, designed for offline AC/DC power supplies. It operates within a supply voltage range of 4.5 V to 24 V and supports switching frequencies between 57 kHz and 78 kHz. The device utilizes valley-switching technology to minimize switching losses and electromagnetic interference (EMI). It features integrated high-voltage startup circuitry, reducing external component count. The unit is housed in a 16-pin SOIC package and functions reliably across an operating temperature range of 0°C to +70°C.

Feature Summary

• Implements quasi-resonant valley-switching operation to enhance efficiency and reduce EMI
• Integrates high-voltage startup circuitry for simplified design
• Supports multiple protection mechanisms including overvoltage, undervoltage, and thermal shutdown

Applications

• Offline AC/DC converters
• Universal input power supplies
• Flyback transformer-based designs

Procurement Notes

Verify the specific suffix against the manufacturer datasheet to confirm pinout compatibility and functional equivalence. Ensure the procurement channel provides valid traceability documentation. Confirm that the component meets current RoHS compliance standards required for your assembly process before finalizing orders.

Selection Notes

Select this controller for applications requiring high efficiency in flyback topologies without complex feedback loops. It is suitable for universal input ranges where low standby power consumption is critical. Consider the thermal performance of the SOIC-16 package relative to the expected power dissipation in your specific enclosure environment.

Part Context

This component belongs to the UC287x series of quasi-resonant controllers from Texas Instruments. These devices are engineered to replace traditional fixed-frequency PWM controllers in flyback applications, offering improved performance through frequency dithering and valley switching capabilities.

Replacement Considerations

Consult official substitution lists for direct replacements such as the UC2871DR or UC3871 variants. Verify pin-to-pin compatibility and electrical parameter alignment with the original design requirements before implementing any alternative part numbers.