NCP1203_05 Datasheet, PDF (1/15 Pages) ON Semiconductor – PWM Current−Mode Controller for Universal Off−Line Supplies Featuring Standby and Short Circuit Protection

NCP1203
PWM Current−Mode
Controller for Universal
Off−Line Supplies Featuring
Standby and Short Circuit
Protection
Housed in SOIC−8 or PDIP−8 package, the NCP1203 represents a
major leap toward ultra−compact Switchmode Power Supplies and
represents an excellent candidate to replace the UC384X devices. Due
to its proprietary SMARTMOSt Very High Voltage Technology, the
circuit allows the implementation of complete off−line AC−DC
adapters, battery charger and a high−power SMPS with few external
components.
With an internal structure operating at a fixed 40 kHz, 60 kHz or
100 kHz switching frequency, the controller features a high−voltage
startup FET which ensures a clean and loss−less startup sequence. Its
current−mode control naturally provides good 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 improved efficiency at light loads
while offering excellent performance in standby conditions. Because
this occurs at a user adjustable low peak current, no acoustic noise
takes place.
The NCP1203 also includes an efficient protective circuitry which,
in presence of an output over load 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. Finally, a
temperature shutdown with hysteresis helps building safe and robust
power supplies.
Features
• High−Voltage Startup Current Source
• Auto−Recovery Internal Output Short−Circuit Protection
• Extremely Low No−Load Standby Power
• Current−Mode with Adjustable Skip−Cycle Capability
• Internal Leading Edge Blanking
• 250 mA Peak Current Capability
• Internally Fixed Frequency at 40 kHz, 60 kHz and 100 kHz
• Direct Optocoupler Connection
• Undervoltage Lockout at 7.8 V Typical
• SPICE Models Available for TRANsient and AC Analysis
• Pin to Pin Compatible with NCP1200
• Pb−Free Packages are Available
Applications
• AC−DC Adapters for Notebooks, etc.
• Offline Battery Chargers
• Auxiliary Power Supplies (USB, Appliances, TVs, etc.)
http://onsemi.com
MARKING
DIAGRAM
8
1
SOIC−8
D1, D2 SUFFIX
CASE 751
8
203Dx
ALYW
G
1
x
= 4, 6, or 1
A
= Assembly Location
L
= Wafer Lot
Y
= Year
W
= Work Week
G
= Pb−Free Package
8
1
PDIP−8
N SUFFIX
CASE 626
8
1203Pxx
AWL
YYWWG
1
xx
= 40, 60, or 100
A
= Assembly Location
WL = Wafer Lot
YY
= Year
WW = Work Week
G
= Pb−Free Package
PIN CONNECTIONS
Adj 1
FB 2
CS 3
GND 4
8 HV
7 NC
6 V_CC
5 Drv
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 13 of this data sheet.
© Semiconductor Components Industries, LLC, 2005
1
October, 2005− Rev. 7
Publication Order Number:
NCP1203/D