NCP1250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 NCP1250 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 its 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. 40W AdapterOver Power Protection (OPP) is a difficult exercise especially when no-load standby requirements drive the converter specifications. The ON proprietary integrated OPP lets you harness the maximum delivered power without affecting your standby performance simply via two external resistors. An Over Voltage Protection input is also combined on the same pin and protects the whole circuitry in case of optocoupler failure or adverse open loop operation. Finally, a timer-based short-circuit protection offers the best protection scheme, letting you precisely select the protection trip point irrespective of a loose coupling between the auxiliary and the power windings.

特性 Features

• Non-dissipative internal and adjustable Over Power Protection (OPP) circuits
• Limits maximum delivered power without affecting standby performance
• Frequency Foldback down to 26 kHz and Skip-Cycle in light load conditions
• High efficiency in light load conditions
• Internal Ramp Compensation
• Reduces the number of external components
• Frequency jittering from full load to skip-cycle
• Improved EMI performance
• Latch input for OVP and OTP implementations
• Simple implementation of required protection functions
• See NCP1251 for integrated Over Voltage Protection (OVP) monitoring on the Vcc pin

应用 Application

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

简介

NCP1250属于集成电路（IC）的ACDC转换器离线开关。由制造生产的NCP1250AC 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。