NCP1200
PWM Current−Mode
Controller for Low−Power
Universal Off−Line Supplies
Housed in SOIC−8 or PDIP−8 package, the NCP1200 represents a
major leap toward ultra−compact Switchmode Power Supplies. Due 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.
Due to current−mode control, the NCP1200 drastically simplifies the
design of reliable and cheap offline converters with extremely low
acoustic generation 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 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.
Features
http://onsemi.com
MARKING
DIAGRAMS
8
SOIC−8
D SUFFIX
CASE 751
1
1
8
PDIP−8
P SUFFIX
CASE 626
8
1
xxx
y
1
= Device Code: 40, 60 or 100
= Device Code:
4 for 40
6 for 60
1 for 100
A
= Assembly Location
L
= Wafer Lot
Y, YY = Year
W, WW = Work Week
G,
G
= Pb−Free Package
1200Pxxx
AWL
YYWWG
200Dy
ALYW
G
8
•
•
•
•
•
•
•
•
•
•
•
•
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
PIN CONNECTIONS
Adj
FB
CS
GND
1
2
3
4
8
7
6
5
HV
NC
V
CC
Drv
(Top View)
Typical Applications
•
AC−DC Adapters
•
Offline Battery Chargers
•
Auxiliary/Ancillary Power Supplies (USB, Appliances, TVs, etc.)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 14 of this data sheet.
©
Semiconductor Components Industries, LLC, 2006
1
September, 2006 − Rev. 15
Publication Order Number:
NCP1200/D
ONSEMI [ ON SEMICONDUCTOR ]
