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
•
•
•
•
•
•
•
•
•
•
•
•
http://onsemi.com
MINIATURE PWM
CONTROLLER FOR HIGH
POWER AC−DC WALL
ADAPTERS AND OFFLINE
BATTERY CHARGERS
MARKING
DIAGRAMS
8
SOIC−8
D SUFFIX
CASE 751
8
1
1
8
1200APyy
AWL
YYWWG
PDIP−8
P SUFFIX
CASE 626
8
1
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
Pb−Free Packages are Available
200Ax
ALYW
G
1
x
yy
A
L, WL
Y, YY
W, WW
G or G
= 1, 4, or 6
= 40, 60, or 100
= Assembly Location
= Wafer Lot
= Year
= Work Week
= Pb−Free Package
PIN CONNECTIONS
FB 2
7 NC
6 VCC
GND 4
• AC−DC Adapters for Portable Devices
• Offline Battery Chargers
• Auxiliary Power Supplies (USB, Appliances, TVs, etc.)
8 HV
CS 3
Typical Applications
Adj 1
5 Drv
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information in the
package dimensions section on page 14 of this data sheet.
© Semiconductor Components Industries, LLC, 2011
January, 2011 − Rev. 9
1
Publication Order Number:
NCP1200A/D
