© Semiconductor Components Industries, LLC, 2006

October, 2006 − Rev. 7

1

Publication Order Number:

NCP1205/D

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

startup sequence without deteriorating the efficiency once off.

The continuous feedback signal monitoring implemented with an

Overcurrent fault Protection circuitry (OCP) makes the final design

rugged and reliable. The PDIP−14 offers an adjustable version of the

OVP threshold via an external resistive network.

Features

Operation (QR)

at Light−Load

Applications

*For additional information on our Pb−Free strategy and soldering details, please

download the ON Semiconductor Soldering and Mounting Techniques

Reference Manual, SOLDERRM/D.

MARKING

DIAGRAM

http://onsemi.com

1

8

1205P

AWL

YYWWG

1

8

A

= Assembly Location

WL

= Wafer Lot

YY, Y

= Year

WW

= Work Week

G

= Pb−Free Package

PDIP−8

N SUFFIX

CASE 626

PDIP−14

P SUFFIX

CASE 646

14

1

1

14

NCP1205P2

AWLYYWWG

SOIC−16

D SUFFIX

CASE 751B

16

1

NCP1205DG

AWLYWW

16

1

Device

Package

ORDERING INFORMATION

NCP1205P

PDIP−8

50 Units/Rail

NCP1205P2

PDIP−14

25 Units/Rail

NCP1205DR2

SOIC−16

2500/Tape & Reel

NCP1205PG

PDIP−8

(Pb−Free)

50 Units/Rail

†For information on tape and reel specifications,

including part orientation and tape sizes, please

refer to our Tape and Reel Packaging Specifications

Brochure, BRD8011/D.

NCP1205P2G

PDIP−14

(Pb−Free)

25 Units/Rail

NCP1205DR2G

SOIC−16

(Pb−Free)

2500/Tape & Reel