【產品特性】• Performance exceeds 5 star EC IPP rating for no-load stand-by power
• Best in class for primary side regulators without the need for opto feedback circuit
• Enables high power density charger designs by reducing magnetics size
• Low loss start-up & allows use of a small VDD bias capacitor
• Lower system BOM cost as compared to MOSFET based solution
【產品應用】• Standby Power supplies in DTV, PC, etc
• USB compliant adapters/chargers for CE
• Tablet PC chargers
• Mobile phone chargers
【文字介紹】The UCC28720 flyback power supply controller provides isolated-output Constant-Voltage (CV) and Constant-Current (CC) output regulation without the use of an optical coupler. The devices process information from the primary power switch and an auxiliary flyback winding for precise control of output voltage and current.
An internal 700-V start-up switch, dynamically-controlled operating states and a tailored modulation profile support ultra-low standby power without sacrificing start-up time or output transient response.
Control algorithms in the UCC28720 allow operating efficiencies to meet or exceed applicable standards. The output drive interfaces to a bipolar transistor power switch. Discontinuous conduction mode (DCM) with valley switching reduces switching losses. Modulation of switching frequency and primary current peak amplitude (FM and AM) keeps the conversion efficiency high across the entire load and line ranges