Description

The UCC28740EVM-525 evaluation module is a 10W off-line discontinuous mode (DCM) flyback converter that provides constant-voltage (CV) and constant-current (CC) output regulation. It uses optical coupler feedback for tight voltage regulation and improved the transient response to large load steps and primary side control for accurate constant current regulation. The UCC28740 controller uses frequency modulation, peak primary current modulation, valley switching and valley skipping in its control algorithm in order to maximize efficiency over the entire operating range.

Features

• Universal AC input, 5V/2.1A output
• <20mW no load power
• Avg. efficiency > 80%
• Opto-Coupled Feedback for Constant Voltage Regulation and Fast Dynamic Response
• Primary Side Control for Tight Constant Current Performance (± 5% Output Current Regulation)
• Internal 700V Start-Up Switch to Start up the Supply Directly From the Bulk Rail
• Quasi-resonant valley switching operation for highest overall efficiency
• Protection Functions: Over Voltage, Low Line, Over Current and Short circuit