描述 Description

The NCP1342 is a highly integrated quasi-resonant flyback controller suitable for designing high-performance off-line power converters. With an integrated active X2 capacitor discharge feature, the NCP1342 can enable no-load power consumption below 30 mW.

The NCP1342 features proprietary valley-lockout circuitry, ensuring stable valley switching.This system works down to the 6th valley and transitions to frequency foldback mode to reduce switching losses.As the load decreases further, the NCP1342 enters quiet-skip mode to manage the power delivery while minimizing acoustic noise.

To ensure light load performance with high frequency designs, the NCP1342 incorporates Minimum Peak Current Modulation (MPCM) to reduce the switching frequency quickly.To help ensure converter ruggedness, the NCP1342 implements several key protective features such as internal brownout detection, a non-dissipative Over Power Protection (OPP) for constant maximum output power regardless of input voltage, a latched overvoltage and NTC-ready overtemperature protection through a dedicated pin, and line removal detection to safely discharge the X2 capacitors when the ac line is removed.

特性 Features

? Minimum Peak Current Modulation for Rapid Frequency Foldback (RFF)
? Fast reduction of switching frequency for improved light load efficiency
? QR Frequency Jittering
? Reduces EMI Signature
? Quiet-Skip Technology
? Ensures Operation Outside Audible Range
? Integrated HV Startup with Brownout Protection
? Provides an efficient power-on source and protects against drops in input mains voltage
? Valley Switching Operaton with Valley Lockout
? Maximizes the efficiency over the entire power range
? Integrated X2 Capacitor Discharge Capability
? Eliminates the need for a X2 resistor
? NTC Compatible Fault Pin
? Extra protection against high temperature or other fault conditions
? High Drive Capability:-500 mA / +800 mA
? Enables faster switching of primary-side MOSFET
? Latch input for OVP and OTP implementation
? Simple implementation of required protection functions

應(yīng)用 Application

? Medium or High Power AC-DC Adapters
? Ultra High Density AC-DC Adapters
? USB PD Compliant
? Notebook Adapters
? Flat TV SMPS
? Computer Power Supplies
? Phone and Tablet Adapters

簡介

NCP1342屬于集成電路（IC）的ACDC轉(zhuǎn)換器離線開關(guān)。由制造生產(chǎn)的NCP1342AC DC 轉(zhuǎn)換器，離線開關(guān)該系列是元器件級控制產(chǎn)品，用于構(gòu)建將交流市電轉(zhuǎn)換為直流電（通常電壓大幅降低）的設(shè)備。集成和未集成系統(tǒng)主要開關(guān)元件的器件均包括在內(nèi)。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(xiàn)此用途，但也有許多專門用于此用途的庫存產(chǎn)品，請參見“開關(guān)轉(zhuǎn)換器，SMPS 變壓器”標題。