NCP1205_06 Datasheet, PDF (1/17 Pages) ON Semiconductor – Single Ended PWM Controller Featuring QR Operation and Soft Frequency Foldback

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 V_CC capacitor and ensures a clean and short
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
• 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 30 V
• Wide UVLO Levels: 7.2 to 15 V Typical
• Auto−Recovery Internal Short−Circuit Protection (OCP)
• Integrated 3.0 mA Typ Startup Source
• Current Mode Control
• Adjustable Overvoltage Level
• Pb−Free Packages are Available*
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.)
*For additional information on our Pb−Free strategy and soldering details, please
download the ON Semiconductor Soldering and Mounting Techniques
Reference Manual, SOLDERRM/D.
8
1
14
1
16
1
http://onsemi.com
MARKING
DIAGRAM
PDIP−8
N SUFFIX
CASE 626
8
1205P
AWL
YYWWG
1
PDIP−14
P SUFFIX
CASE 646
14
NCP1205P2
AWLYYWWG
1
16
SOIC−16
D SUFFIX
CASE 751B
NCP1205DG
AWLYWW
1
A
WL
YY, Y
WW
G
= Assembly Location
= Wafer Lot
= Year
= Work Week
= Pb−Free Package
ORDERING INFORMATION
Device
Package
Shipping^†
NCP1205P
PDIP−8
50 Units/Rail
NCP1205PG
PDIP−8
(Pb−Free)
50 Units/Rail
NCP1205P2
PDIP−14
25 Units/Rail
NCP1205P2G
PDIP−14
(Pb−Free)
25 Units/Rail
NCP1205DR2
SOIC−16 2500/Tape & Reel
NCP1205DR2G
SOIC−16 2500/Tape & Reel
(Pb−Free)
†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.
© Semiconductor Components Industries, LLC, 2006
1
October, 2006 − Rev. 7
Publication Order Number:
NCP1205/D