DataSheetWiki


NCP1237 fiches techniques PDF

ON Semiconductor - Fixed Frequency Current Mode Controller

Numéro de référence NCP1237
Description Fixed Frequency Current Mode Controller
Fabricant ON Semiconductor 
Logo ON Semiconductor 





1 Page

No Preview Available !





NCP1237 fiche technique
NCP1237
www.DataSheet4U.com
Fixed Frequency Current
Mode Controller for Flyback
Converters
The NCP1237 is a new generation of the NCP12xx fixedfrequency
currentmode controllers featuring Dynamic SelfSupply (DSS),
pintopin compatible with the previous generation.
The DSS function greatly simplifies the design of the auxiliary supply
and the VCC capacitor by activating the internal startup current source to
supply the controller during transients.
Due to its proprietary SoftSkipmode combined with frequency
foldback, the controller exhibits excellent efficiency in light load
condition while still achieving very low standby power consumption.
This SoftSkip feature also dramatically reduces the risk of acoustic
noise, which enables the use of inexpensive transformers and
capacitors in the clamping network.
The NCP1237 features a duallevel timerbased fault detection that
controls the amount of transient peak power that the controller can
deliver for a limited time.
Internal frequency jittering, ramp compensation, and a versatile
latch input make this controller an excellent candidate for converters
where ruggedness and components cost are the key constraints.
In addition, the controller includes a new high voltage circuitry that
combines a startup current source and a brownout / line OVP detector
able to sense the input voltage either from the rectified ac line or the dc
filtered bulk voltage.
Finally, due to a careful design, the precision of critical parameters
is well controlled over the entire temperature range (40°C to
+125°C), enabling easier design and increased safety (e.g. ±5% for the
peak current limit, ±7% for the oscillator).
http://onsemi.com
MARKING
DIAGRAM
SOIC7
CASE 751U
8
37Xff
ALYWX
G
1
37Xff = Specific Device Code
X = A or B
ff = 65, 00, or 33
A = Assembly Location
L = Wafer Lot
Y = Year
W = Work Week
G = PbFree Package
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 32 of this data sheet.
Features
TimerBased Transient Power and Overload
Protections with AutoRecovery (Option B) or Latched
(Option A) Operation
HighVoltage Current Source with DSS with Builtin
Brownout and Line Overvoltage Protections
FixedFrequency CurrentMode Operation with
Builtin Ramp Compensation
Frequency Jittering for a Reduced EMI Signature
Adjustable Overpower Compensation
Latchoff Input for Severe Fault Conditions, with
Direct Connection of an NTC for Overtemperature
Protection (OTP)
Protection Against Winding ShortCircuit
Frequency Foldback transitioning into SoftSkip for
Improved Performance in Standby
65 kHz Oscillator (100 kHz and 133 kHz Versions
Available Upon Request)
VCC Operation up to 28 V
Increased Precision on Critical Parameters
±1.0 A Peak Drive Capability
4.0 ms SoftStart
Internal Thermal Shutdown with Hysteresis
These Devices are PbFree, Halogen Free/BFR Free
and are RoHS Compliant*
Typical Applications
acdc Adapters for Notebooks, LCD, and Printers
Offline Battery Chargers
Consumer Electronic Power Supplies
Auxiliary/Housekeeping Power Supplies
*For additional information on our PbFree strategy and soldering details, please
download the ON Semiconductor Soldering and Mounting Techniques
Reference Manual, SOLDERRM/D.
© Semiconductor Components Industries, LLC, 2010
February, 2010 Rev. 1
1
Publication Order Number:
NCP1237/D

PagesPages 30
Télécharger [ NCP1237 ]


Fiche technique recommandé

No Description détaillée Fabricant
NCP1230 Low Standby Power High Performance PWM Controller ON Semiconductor
ON Semiconductor
NCP1230A Low-Standby Power Soft Skip Mode Controller ON Semiconductor
ON Semiconductor
NCP1231 Low Standby Power High Performance PWM Controller ON Semiconductor
ON Semiconductor
NCP1232 Microprocessor Monitor ON
ON

US18650VTC5A

Lithium-Ion Battery

Sony
Sony
TSPC106

PCI Bus Bridge Memory Controller

ATMEL
ATMEL
TP9380

NPN SILICON RF POWER TRANSISTOR

Advanced Semiconductor
Advanced Semiconductor


www.DataSheetWiki.com    |   2020   |   Contactez-nous  |   Recherche