描述 Description

Housed in SO-8 or DIP-8 package, the NCP1200 represents a major leap toward ultra-compact Switch-Mode Power Supplies. Thanks to a novel concept, the circuit allows the implementation of a complete offline battery charger or a standby SMPS with few external components. Furthermore, an integrated output short-circuit protection lets the designer build an extremely low-cost AC/DC wall adapter associated with a simplified feedback scheme.With an internal structure operating at a fixed 40 kHz, 60 kHz or 100 kHz, the controller drives low gate-charge switching devices like an IGBT or a MOSFET thus requiring a very small operating power. Thanks to current-mode control, the NCP1200 drastically simplifies the design of reliable and cheap offline converters with excellent audio- susceptibility and inherent pulse-by-pulse control.When the current setpoint falls below a given value, e.g. the output power demand diminishes, the IC automatically enters the so-called skip cycle mode and provides excellent efficiency at light loads. Because this occurs at low peak current, no acoustic noise takes place.Finally, the IC is self-supplied from the DC rail, eliminating the need of an auxiliary winding. This feature ensures operation in presence of low output voltage or shorts.

特性 Features

No Auxiliary Winding Operation
Internal Output Short-Circuit Protection
Extremely Low No-Load Standby Power
Current-Mode with Skip-Cycle Capability
Internal Leading Edge Blanking
250 mA Peak Current Source/Sink Capability
Internally Fixed Frequency at 40 kHz, 60 kHz and 100 kHz
Direct Optocoupler Connection
Built-in Frequency Jittering for Lower EMI
SPICE Models Available for TRANsient and AC Analysis
Internal Temperature Shutdown
Pb-Free Packages are Available

應(yīng)用 Application

AC/DC AdaptersOffline Battery ChargersAuxiliary/Ancillary Power Supplies (USB, Appliances, TVs, etc.)

簡介

NCP1200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NCP1200AC 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存產(chǎn)品，請(qǐng)參見“開關(guān)轉(zhuǎn)換器，SMPS 變壓器”標(biāo)題。