• - 交流-直流(AC-DC)控制器和稳压器
• - 直流-直流(DC-DC)控制器、转换器和稳压器
• - 电压和电流管理
• - 通讯IC
• - 驱动器
• - 热管理

• - 时钟及数据分配
• - 标准逻辑

• - 放大器和比较器
• - 模拟开关
• - 数字电位计
• - 接口
• - EMI和RFI滤波器

• - EEPROM存储器
• - 非易失性只读存储器(NVRAM)
• - SRAM存储器

说明

The UCC28521 and UCC28528 combination PFC/PWM controllers provide complete control functionality for any off-line power system requiring compliance with the IEC1000-3-2 harmonic reduction requirements. By combining the control and drive signals for the PFC and the PWM stages into a single device, significant performance and cost benefits are gained.

Based on the UCC28511, the new devices employ an average current mode control architecture with input voltage feedforward. The major difference of the UCC28521/28 is the trailing-edge / trailing-edge (TEM/TEM) modulation scheme for the PFC/PWM stages. The UCC28528 differs from the UCC28521 as its PWM stage does not turn off with the falling bulk voltage. The UCC28528 PWM was designed for low power auxiliary supplies.

特性

• Provides Control of PFC and PWM Power Stages In One Device
• Trailing-Edge PFC, Trailing-Edge PWM Modulation
• Built-In Sequencing of PFC and PWM Turn-On
• 2-A Source and 3-A Sink Gate Drive for Both PFC and PWM Stages
• Typical 16-ns Rise Time and 7-ns Fall Time into 1-nF Loads
• PFC Features
  • Average-Current-Mode Control for Continuous Conduction Mode Operation
  • Highly-Linear Multiplier for Near-Unity Power Factor
  • Input Voltage Feedforward Implementation
  • Improved Load Transient Response
  • Accurate Power Limiting
  • Zero Power Detect
• PWM Features
  • Peak-Current-Mode Control Operation
  • 1:1 PFC:PWM Frequency Option
  • Programmable maximum Duty Cycle Limit Up to 90%
  • Programmable Soft-Start
• APPLICATIONS
  • High-Efficiency Server and Desktop Supplies
  • High-Efficiency Telecom AC-DC Converter