The UCC28740 isolated-flyback power-supply controller provides Constant-Voltage (CV) using an optical coupler to improve transient response to large load steps. Constant-Current (CC) regulation is accomplished through Primary-side Regulation (PSR) techniques. This device processes information from opto-coupled feedback and an auxiliary flyback winding for precise high-performance control of
output voltage and current.
FEATURES
• Less than 10-mW No-Load Power Capability
• Opto-Coupled Feedback for CV, and Primary-Side Regulation (PSR) for CC
• Enables ±1% Voltage Regulation and ±5% Current Regulation Across Line and Load
• 700-V Startup Switch
• 100-kHz Maximum Switching Frequency Enables High-Power-Density Charger Designs
• Resonant-Ring Valley-Switching Operation for Highest Overall Efficiency
• Frequency Dithering to Ease EMI Compliance
• Clamped Gate-Drive Output for MOSFET
• Overvoltage, Low-Line, and Overcurrent Protection Functions
• SOIC-7 Package
APPLICATIONS
• USB-Compliant Adapters and Chargers for Consumer Electronics