AN826 数据手册 ( 数据表 ) - STMicroelectronics

INTRODUCTION
This application has been designed to provide a complete supply for colour TV. The system has been configured using a Flyback DC-DC converter with an upstream PFC section in order to improve the characteristics of the whole supply. The architecture of the system consists of a L4981A controller with the relevant circuitry for the PFC section, and of a TEA2261 synchronised, in master-slave configuration, with a TEA5170 at 15 kHz switching frequency. When the supply is in stand-by condition, the TEA2261 controller operates in burst mode.

System Main Features:
■ Input Voltage Range: 176 to 270 Vac
■ Rated Output Power: 250W
■ Power Factor at max. Output Power: 0.98
■ Input Power in Stand-by mode: 3W
■ DC Preregulated Voltage: 400
■ Efficiency: > 80%
■ Operating Frequency: 15kHZ Synchronised (only Fly-Back Section)
■ Minimum Output Power Synchronised : 8.5 W
■ Others: Short Circuit, Overload and Open Load Protection.