NCP1253数据手册集成电路（IC）的ACDC转换器离线开关规格书PDF

描述 Description

The NCP1253 is a highly integrated PWM controller capable of delivering a rugged and high performance offline power supply in a tiny TSOP-6 package. With a supply range up to 28 V, the controller hosts a jittered 65 kHz or 100 kHz switching circuitry operated in peak current mode control. When the power on the secondary side starts to decrease, the controller automatically folds back it's switching frequency down to a minimum level of 26 kHz. As the power further goes down, the part enters skip cycle while limiting the peak current. To avoid sub harmonic oscillations in CCM operation, adjustable slope compensation is available via the series inclusion of a simple resistor in the current sense signal. Besides the auto-recovery timer-based short-circuit protection, an Over Voltage Protection on the Vcc pin protects the whole circuitry in case of optocoupler destruction or adverse open loop operation.

特性 Features

• Frequency Foldback down to 26 kHz and Skip-Cycle in Light Load
• Improved efficiency across the load range
• Internal Ramp Compensation
• Reduces the number of external components
• Frequency Jittering in Normal and Frequency Foldback modes
• Low EMI signature
• Over Voltage Protection (OVP) monitoring on the Vcc pin
• Protects against output over voltage conditions without any added components
• Timer-based Auto-Recovery or Latched Short-Circuit Protection
• Protection against fault conditions

应用 Application

• Offline Adapters
• AC-DC converters
• Set-top Boxes
• Printers
• Notebooks and Netbooks

简介

NCP1253属于集成电路（IC）的ACDC转换器离线开关。由制造生产的NCP1253AC DC 转换器，离线开关该系列是元器件级控制产品，用于构建将交流市电转换为直流电（通常电压大幅降低）的设备。集成和未集成系统主要开关元件的器件均包括在内。由于高输入输出电压比，以及此类系统中通常需要隔离，这些器件通常与外部变压器配合使用。尽管通常使用定制变压器来实现此用途，但也有许多专门用于此用途的库存产品，请参见“开关转换器，SMPS 变压器”标题。