描述 Description

The NCP1079A & NCP1079B products integrate a fixed frequency current mode controller with a 700 V MOSFET. Available in a two different pin out of the very common PDIP 7 package, it offers a high level of integration, including soft start, frequency jittering, short circuit protection, skip cycle, a maximum peak current set point, ramp compensation, and a dynamic self supply (DSS, eliminating the need for an auxiliary winding).Unlike other monolithic solutions, the NCP1079A & NCP1079B is quiet by nature: during nominal load operation, the part switches at one of the available frequencies (65 or 100 kHz). When the output power demand diminishes, the IC automatically enters frequency foldback mode and provides excellent efficiency at light loads. When the power demand reduces further, it enters into a skip mode to reduce the standby consumption down to a no load condition.Protection features include: a timer to detect an overload or a short circuit event, Over voltage Protection with auto recovery. Ac input line voltage detection prevents lethal runaway in low input voltage conditions (Brown-out) as well as too high an input line (Ac line Over voltage Protection). This also allows an Over power Protection to compensate all internal delays in high input voltage conditions and optimize the maximum output current capability.For improved standby performance, the connection of an auxiliary winding stops the DSS operation and helps to reduce input power consumption below 50 mW at high line.

特性 Features

? Integrated 700 V MOSFET with RDS(on) of 2.7 Ω
? Up to 30W output SMPS design capability
? Current-Mode Fixed Frequency Operation (65 & 100 kHz)- 130 kHz for B version only
? Ability to scale for efficiency or size
? Peak Current: NCP1079A/B = 1,050mA
? Adjust output current protection based on output power demand
? Skip-Cycle Operation at Low Peak Current
? Eliminate acoustic noise
? Dynamic Self-Supply (DSS)
? Eliminate Aux winding
? Auto-Recovery Output Short Circuit Protection with Timer-Based Detection
? Provides more robust protection without worrying about the coupling of the aux winding
? Frequency Foldback Operation
? Improved efficiency at light load / Improved EMI over the entire load
? 300 μA No Load Power Consumption
?
? Frequency Jittering (including during frequency foldback mode)
? Better EMI Signature Over the Entire Operating Range
? Adjustable Brown-out Protection and OVP
? Enhanced Protection Against too Low or too High Input Voltage
? Over Power Protection
? Higher Protection of the load in wide Mains Conditions
? 2nd Level Current Protection
? Protection in case of secondary diode short

應用 Application

? Auxiliary & Standby Power Supply
? Major Home Appliances power supplies
? Low to medium Power Chargers & Adapters
? White Goods
? E-Meters
? Industrial
? Consumer Equipment Power Supply

簡介

NCP1079A屬于集成電路（IC）的ACDC轉換器離線開關。由制造生產的NCP1079AAC DC 轉換器，離線開關該系列是元器件級控制產品，用于構建將交流市電轉換為直流電（通常電壓大幅降低）的設備。集成和未集成系統(tǒng)主要開關元件的器件均包括在內。由于高輸入輸出電壓比，以及此類系統(tǒng)中通常需要隔離，這些器件通常與外部變壓器配合使用。盡管通常使用定制變壓器來實現此用途，但也有許多專門用于此用途的庫存產品，請參見“開關轉換器，SMPS 變壓器”標題。