Semiconductor Components Industries, LLC, 2005
January, 2005− Rev. 7
1 Publication Order Number:
NCP1200A/D
NCP1200A
PWM Current−Mode
Controller for Universal
Off−Line Supplies Featuring
Low Standby Power
Housed in SOIC−8 or PDIP−8 package, the NCP1200A enhances
the previous NCP1200 series by offering a reduced optocoupler
current together with an increased drive capability. Due to its novel
concept, the circuit allows the implementation of complete off−line
AC−DC adapters, battery charger or a SMPS where standby power is a
key parameter.
With an internal structure operating at a fixed 40 kHz, 60 kHz 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 task in battery charger applications. Finally,
current−mode control provides an excellent audio−susceptibility 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 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.
The NCP1200A features an efficient protective circuitry which, in
presence of an overcurrent condition, disables the output pulses while
the device enters a safe burst mode, trying to restart. Once the default
has gone, the device auto−recovers.
Features
• Pb−Free Packages are Available
• No Auxiliary Winding Operation
• Auto−Recovery Internal Output Short−Circuit Protection
• Extremely Low No−Load Standby Power
• Current−Mode Control with Skip−Cycle Capability
• Internal Temperature Shutdown
• Internal Leading Edge Blanking
• 250 mA Peak Current Capability
• Internally Fixed Frequency at 40 kHz, 60 kHz and 100 kHz
• Direct Optocoupler Connection
• SPICE Models Available for TRANsient and AC Analysis
• Pin to Pin Compatible with NCP1200
Typical Applications
• AC−DC Adapters for Portable Devices
• Offline Battery Chargers
• Auxiliary Power Supplies (USB, Appliances, TVs, etc.)
SOIC−8
D SUFFIX
CASE 751
1
8
MARKING
DIAGRAMS
PIN CONNECTIONS
PDIP−8
P SUFFIX
CASE 626
1
8
1
8
1200APxxx
AWL
YYWW
200Ay
ALYW
xxx = Specific Device Code
(40, 60 or 100)
y = Specific Device Code
(4 for 40, 6 for 60, 1 for 100)
A = Assembly Location
WL, L = Wafer Lot
Y, YY = Year
W, WW = Work Week
1
Adj
8
HV
2
FB
3
CS
4
GND
7
NC
6
V
CC
5
Drv
(Top View)
MINIATURE PWM
CONTROLLER FOR HIGH
POWER AC−DC WALL
ADAPTERS AND OFFLINE
BATTERY CHARGERS
See detailed ordering and shipping information in the package
dimensions section on page 14 of this data sheet.
ORDERING INFORMATION
http://onsemi.com
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