©
Semiconductor Components Industries, LLC, 2005
October, 2005 − Rev. 5
1
Publication Order Number
NCP1239/D
NCP1239
Low−Standby High
Performance PWM Controller
Housed in SO−16 the NCP1239 represents a major leap toward
ultra−compact Switch Mode Power Supplies specifically tailored for
medium to high power off−line applications, e.g. notebook adapters.
The NCP1239 offers everything needed to build a rugged and efficient
power supply, including a dedicated event management to drive a
Power Factor Correction (PFC) front−end circuitry. The circuit
disables the front−end PFC stage while still in fault or standby
conditions by interrupting the PFC controller powering for improved
no−load consumption figures. As soon as normal operating mode
recovers, the NCP1239 feeds back the PFC that wakes−up.
When power demand is low, the IC automatically enters the
so−called skip−cycle mode and provides excellent efficiency at light
loads. Because this occurs at a user adjustable low peak current, no
acoustic noise takes place.
Features
•
Current−Mode Operation with Internal Ramp Compensation
•
Internal High−Voltage Current Source for loss−less Startup
•
Adjustable Skip−Cycle Capability
•
Selectable Soft−Start Period
•
Internal Frequency Dithering for Improved EMI Signature
•
Go−to−Standby Signal for PFC Front−Stage
•
Large V
CC
Operation from 12.2 V to 36 V
•
500 mV Overcurrent Limit
•
500 mA/−800 mA Peak Current Capability
•
5 V/10 mA Pinned−out Reference Voltage
•
Adjustable Switching Frequency up to 250 kHz.
•
Overload Protection Independent of the Auxiliary V
CC
•
Adjustable Over Power Compensation (NCP1239F)
•
Programmable Maximum Duty Cycle (NCP1239V)
•
Pb−Free Packages are Available*
Typical Applications
•
High Power AC/DC Adapters for Notebooks etc.
•
Offline Battery Chargers
•
Telecom and PC Power Supplies
•
Flyback Applications (NCP1239F) and Forward Applications
(NCP1239V)
*For additional information on our Pb−Free strategy and soldering details, please
download the ON Semiconductor Soldering and Mounting Techniques
Reference Manual, SOLDERRM/D.
NCP1239xD = Device Code
x
= F or V
A
= Assembly Location
WL
= Wafer Lot
Y
= Year
WW
= Work Week
G
= Pb−Free Package
MARKING DIAGRAM
16
SO−16
FD or VD SUFFIX
CASE 751B
NCP1239xDG
AWLYWW
1
1
16
http://onsemi.com
PIN CONNECTIONS
Over Power
Limit
FB
1
16
CS
Skip Adjust
GND
SS/Timer
Drv
Brown−out
V
CC
Rt
NC
Fault Detect
NC
REF5V
HV
GTS
Max Duty−
Cycle
FB
1
16
CS
Skip Adjust
GND
SS/Timer
Drv
Brown−out
V
CC
Rt
NC
Fault Detect
NC
REF5V
HV
GTS
NCP1239F
NCP1239V
See detailed ordering and shipping information in the package
dimensions section on page 5 of this data sheet.
ORDERING INFORMATION
