NCP1205(2002) Просмотр технического описания (PDF) - ON Semiconductor

Номер в каталоге

Компоненты Описание

производитель

NCP1205
(Rev.:2002)

Single Ended PWM Controller Featuring QR Operation and Soft Frequency Foldback

ON Semiconductor 

NCP1205

Single Ended PWM

Controller Featuring QR

Operation and Soft

Frequency Foldback

The NCP1205 combines a true Current Mode Control modulator

and a demagnetization detector to ensure full Discontinuous

Conduction Mode in any load/line conditions and minimum drain

voltage switching (Quasi–Resonant operation, also called critical

conduction operation). With its inherent Variable Frequency Mode

(VFM), the controller decreases its operating frequency at constant

peak current whenever the output power demand diminishes.

Associated with automatic multiple valley switching, this unique

architecture guarantees minimum switching losses and the lowest

power drawn from the mains when operating at no–load conditions.

Thus, the NCP1205 is optimal for applications targeting the newest

International Energy Agency (IEA) recommendations for standby

power.

The internal High–Voltage current source provides a reliable

charging path for the VCC capacitor and ensures a clean and short

start–up sequence without deteriorating the efficiency once off.

The continuous feedback signal monitoring implemented with an

Over–Current fault Protection circuitry (OCP) makes the final design

rugged and reliable. An internal Over Voltage Protection (OVP) circuit

continuously monitors the VCC pin and stops the IC whenever its level

exceeds 36 V. The DIP14 offers an adjustable version of the OVP

threshold via an external resistive network.

Features

• Natural Drain Valley Switching for Lower EMI and Quasi–Resonant

Operation (QR)

• Smooth Frequency Foldback for Low Standby and Minimum Ripple

at Light–Load

• Adjustable Maximum Switching Frequency

• Internal 200 ns Leading Edge Blanking on Current Sense

• 250 mA Sink and Source Driver

• Wide Operating Voltages: 8.0 to 36 V

• Wide UVLO Levels: 7.2 to 15 V Typical

• Auto–Recovery Internal Short–Circuit Protection (OCP)

• Integrated 3.0 mA Typ. Start–Up Source

• Current Mode Control

• Adjustable Over–Voltage Level

• Available in DIP8 and DIP14 Package

Applications

• High Power AC/DC Adapters for Notebooks, etc.

• Offline Battery Chargers

• Power Supplies for DVD, CD Players, TVs, Set–Top Boxes, etc.

• Auxiliary Power Supplies (USB, Appliances, etc.)

8

1

http://onsemi.com

PDIP–8

N SUFFIX

CASE 626

MARKING

DIAGRAMS

8

NCP1205P

AWL

YYWW

1

14

1

14

PDIP–14

P SUFFIX

CASE 646

NCP1205P2

AWLYYWW

1

A = Assembly Location

WL = Wafer Lot

YY = Year

WW = Work Week

ORDERING INFORMATION

Device

Package

Shipping

NCP1205P

PDIP–8

50 Units/Rail

NCP1205P2

PDIP–14

25 Units/Rail

© Semiconductor Components Industries, LLC, 2002

1

April, 2002 – Rev. 2

Publication Order Number:

NCP1205/D

Share Link: