DESCRIPTION
●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
●– Smart Phones
●– Tablet Computers
●– Cameras
●• Standby Supply for TV and Desktop
●• White Goods