©
Semiconductor Components Industries, LLC, 2006
February, 2006 − Rev. 4
1
Publication Order Number:
NCP1201/D
NCP1201
PWM Current−Mode
Controller for Universal
Off−Line Supplies Featuring
Low Standby Power with
Fault Protection Modes
Housed in SOIC−8 or PDIP−8 package, the NCP1201 enhances the
previous NCP1200 series by offering a reduced optocoupler current with
additional Brownout Detection Protection (BOK). Similarly, the circuit
allows the implementation of complete off−line AC−DC adapters, battery
chargers or Switchmode Power Supplies (SMPS) where standby power is
a key parameter.
The NCP1201 features efficient protection circuitry. When in the
presence of a fault (e.g. failed optocoupler, overcurrent condition, etc.)
the control permanently disables the output pulses to avoid subsequent
damage to the system. The IC only restarts when the user cycles the
mains power supply.
With the low power internal structure, operating at a fixed
60 or 100 kHz, the controller supplies itself from the high−voltage rail,
avoiding the need of an auxiliary winding. This feature naturally eases
the designer’s task in battery charger applications. Finally, current−mode
control provides an excellent audio−susceptibility and inherent
pulse−by−pulse control.
When the load current falls down to a pre−defined setpoint (V
SKIP
)
value, e.g. the output power demand diminishes, the IC automatically
enters the skip cycle mode and can provide excellent efficiency under
light load conditions. The skip mode is designed to operate at relatively
lower peak current so that acoustic noise that commonly takes place will
not happen with NCP1201.
Features
•
AC Line Brownout Detect Protection, BOK Function
•
Latchoff Mode Fault Protection
•
No Auxiliary Winding Operation
•
Internal Output Short−Circuit Protection
•
Extremely Low No−Load Standby Power
•
Current−Mode with Skip−Cycle Capability
•
Internal Overtemperature Shutdown
•
Internal Leading Edge Blanking
•
250 mA Gate Peak Current Driving Capability
•
Internally Fixed Switching Frequency at 60 or 100 kHz
•
Built−in Frequency Jittering for EMI Reduction
•
Direct Optocoupler Connection
•
Pb−Free Packages are Available
Typical Applications
•
AC−DC Adapters
•
Offline Battery Chargers
•
Auxiliary Power Supplies (USB, Appliances, TVs, etc.)
1
8
5
3
4
(Top View)
BOK
CS
HV
PIN CONNECTIONS
7
6
2
NC
FB
GND
DRV
VCC
x
= Device Code: 6 for 60 kHz
y
1 for 100 kHz
y
= Device Code: 6 for 60 kHz
xx
10 for 100 kHz
A
= Assembly Location
L
= Wafer Lot
Y, YY
= Year
W, WW = Work Week
G
or G
= Pb−Free Package
See detailed ordering and shipping information in the package
dimensions section on page 17 of this data sheet.
ORDERING INFORMATION
http://onsemi.com
SOIC−8
D SUFFIX
CASE 751
1
8
MARKING
DIAGRAMS
PDIP−8
P SUFFIX
CASE 626
1
8
1
8
1201Py0
AWL
YYWWG
201Dx
ALYW
G
1
8
