NCP1201
PWM Current−Mode
Controller for Universal
Off−Line Supplies Featuring
Low Standby Power with
Fault Protection Modes
http://onsemi.com
MARKING
DIAGRAMS
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.
8
SOIC−8
D SUFFIX
CASE 751
201Dx
ALYW
G
8
1
1
8
1
PDIP−8
P SUFFIX
CASE 626
1201Py0
AWL
YYWWG
8
1
x
y
= Device Code: 6 for 60 kHz
1 for 100 kHz
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.
y
= Device Code: 6 for 60 kHz
10 for 100 kHz
= Assembly Location
= Wafer Lot
xx
A
L
Y, YY = Year
W, WW = Work Week
G or G = Pb−Free Package
Features
• AC Line Brownout Detect Protection, BOK Function
• Latchoff Mode Fault Protection
• No Auxiliary Winding Operation
PIN CONNECTIONS
• Internal Output Short−Circuit Protection
• Extremely Low No−Load Standby Power
• Current−Mode with Skip−Cycle Capability
• Internal Overtemperature Shutdown
• Internal Leading Edge Blanking
BOK
FB
1
2
3
4
8
7
6
5
HV
NC
VCC
DRV
CS
GND
• 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
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 17 of this data sheet.
• Pb−Free Packages are Available
Typical Applications
• AC−DC Adapters
• Offline Battery Chargers
• Auxiliary Power Supplies (USB, Appliances, TVs, etc.)
© Semiconductor Components Industries, LLC, 2006
1
Publication Order Number:
February, 2006 − Rev. 4
NCP1201/D