描述 Description

The NCP1129 switcher offers everything needed to build reliable and compact AC-DC switching power supplies with minimal surrounding elements. Incorporating an avalanche rated 650 V MOSFET, converters built with the NCP1129 can be safely designed for international conditions without jeopardizing the overall reliability. The NCP1129 implements peak current mode control with adjustable ramp compensation that ensures stability in Continuous Conduction Mode (CCM) operation. With an external resistor, the maximum peak current is adjustable, allowing the designer the ability to inject ramp compensation to stabilize CCM power supplies. A short circuit fault condition is independently detected from the auxiliary winding voltage resulting in improved short circuit protection with true overload detection. The Source pin provides access to the MOSFET source, allowing for overpower compensation. With a supply range up to 26 V, the switcher also provides a jittered 65 kHz or 100 kHz switching frequency operated in peak current mode control. When the power on the secondary side starts to decrease, the switcher 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.

特性 Features

? 650 V Avalanche Rated MOSFET
? Rugged MOSFET for robust design
? FixedFrequency 65 or 100 kHz CurrentMode Control Operation
? Ability to scale for efficiency or size
? Frequency Foldback Down to 26 kHz and SkipCycle in Light Load Conditions
? Eliminate acoustic noise and improved efficiency at light loads
? Adjustable Current Limit
? Scale for various designs 5W~20W
? 50 ms Timer-Based Auto-Recovery Short-Circuit Protection
? Provides more robust protection without worrying about the coupling of the aux winding
? Frequency Jittering in Normal and Frequency Foldback Modes
? Improved efficiency at light load / Improved EMI over the entire load
? Option for Auto-Recovery or Latched Short-Circuit Protection
? Flexible protection options
? Less than 100 mW Standby Power at High Line
? EPS 2.0 Compliant

應(yīng)用 Application

? Power Supply
? Power supply for DVD, STB, CD-Player
? Aux supply for TV, USB, Appliance

簡(jiǎn)介

NCP1129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NCP1129AC DC 轉(zhuǎn)換器，離線開關(guān)該系列是元器件級(jí)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(shí)現(xiàn)此用途，但也有許多專門用于此用途的庫(kù)存產(chǎn)品，請(qǐng)參見“開關(guān)轉(zhuǎn)換器，SMPS 變壓器”標(biāo)題。