• - 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 UC28023 and UC28025 are fixed-frequency PWM controllers optimized for high-frequency switched-mode power supply applications. The UC28023 is a single output PWM for single-ended topologies while the UC28025 offers dual alternating outputs for double-ended and full bridge topologies.

Targeted for cost effective solutions with minimal external components, UC2802x include an oscillator, a temperature compensated reference, a wide band width error amplifier, a high-speed current-sense comparator and high-current active-high totem-pole outputs to directly drive external MOSFETs.

Protection circuitry includes a current limit comparator with a 1-V threshold, a TTL compatible shutdown port, and a soft-start pin which will double as a maximum duty cycle clamp.

特性

• Peak Current Mode, Average Current Mode, or Voltage Mode
  (with Feed-Forward) Control Methods
• Practical Operation Up to 1 MHz
• 50-ns Propagation Delay to Output
• ±1.5-A Peak Totem Pole Outputs
• 9-V to 30-V Nominal Operational Voltage Range
• Wide Bandwidth Error Amplifier
• Fully Latched Logic with Double Pulse Suppression
• Pulse-by-Pulse Current Limiting
• Programmable Maximum Duty Cycle Control
• Under-Voltage Lockout with Hysteresis
• Trimmed 5.1-V Reference with UVLO
• Same Functionality as UC3823 and UC3825
• APPLICATIONS
  • Off-Line and DC/DC Power Supplies
  • Converters Using Voltage Mode, Peak Current Mode,
    or Average Current Mode Control Methods
  • Single-Ended or Two-Switch Topology Designs