|
NCP1379_11 Datasheet, PDF (1/22 Pages) ON Semiconductor – Quasi-Resonant Current-Mode Controller for High-Power Universal Off-line Supplies | |||
|
NCP1379
Quasi-Resonant
Current-Mode Controller for
High-Power Universal
Off-line Supplies
The NCP1379 hosts a highâperformance circuitry aimed to
powering quasiâresonant converters. Capitalizing on a proprietary
valleyâlockout system, the controller shifts gears and reduces the
switching frequency as the power loading becomes lighter. This
results in a stable operation despite switching events always occurring
in the drainâsource valley. This system works down to the 4th valley
and toggles to a variable frequency mode beyond, ensuring an
excellent standby power performance.
The controller includes an Over Power Protection circuit which
clamps the delivered power at highâline. Safetyâwise, a fixed internal
timer relies on the feedback voltage to detect a fault. Once the timer
elapses, the controller stops and enters autoârecovery mode, ensuring
a low dutyâcycle burst operation. To further improve the safety of the
power supply, the NCP1379 features a pin to implement a combined
brownâout/overvoltage protection.
Particularly well suited for TVs power supply applications, the
controller features a low startup voltage allowing the use of an
auxiliary power supply to power the device.
Features
⢠QuasiâResonant Peak CurrentâMode Control Operation
⢠Valley Switching Operation with ValleyâLockout for NoiseâImmune
Operation
⢠Frequency Foldback at Light Load to Improve the Light Load
Efficiency
⢠Adjustable Over Power Protection
⢠AutoâRecovery Output ShortâCircuit Protection
⢠Fixed Internal 80 ms Timer for ShortâCircuit Protection
⢠Combined Overvoltage Protection and Brownâout
⢠+500 mA / â800 mA Peak Current Source/Sink Capability
⢠Internal Temperature Shutdown
⢠Direct Optocoupler Connection
⢠Low VCC(on) Allowing to Use a Standby Power Supply to Power the
Device
⢠Extremely Low NoâLoad Standby Power
⢠SO8 Package
⢠These Devices are PbâFree and are RoHS Compliant
Typical Applications
⢠High Power acâdc Converters for TVs, SetâTop Boxes etc.
⢠Offline Adapters for Notebooks
http://onsemi.com
QUASIâRESONANT PWM
CONTROLLER FOR HIGH
POWER ACâDC WALL AD-
APTERS
8
1
SOICâ8
D SUFFIX
CASE 751
MARKING
DIAGRAMS
8
1379
ALYW
G
1
1379
A
L
Y
W
G
= Specific Device Code
= Assembly Location
= Wafer Lot
= Year
= Work Week
= PbâFree Package
PIN CONNECTIONS
ZCD 1
FB 2
CS 3
GND 4
8 CT
7 FAULT
6 VCC
5 DRV
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 21 of this data sheet.
© Semiconductor Components Industries, LLC, 2011
1
July, 2011 â Rev. 2
Publication Order Number:
NCP1379/D
|
▷ |