Electronic Components Datasheet Search |
|
NCP1237 Datasheet(PDF) 1 Page - ON Semiconductor |
|
NCP1237 Datasheet(HTML) 1 Page - ON Semiconductor |
1 / 34 page © Semiconductor Components Industries, LLC, 2010 February, 2010 − Rev. 1 1 Publication Order Number: NCP1237/D NCP1237 Fixed Frequency Current Mode Controller for Flyback Converters The NCP1237 is a new generation of the NCP12xx fixed−frequency current−mode controllers featuring Dynamic Self−Supply (DSS), pin−to−pin 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 Soft−Skip ™ mode combined with frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. This Soft−Skip 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 dual−level timer−based 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 brown−out / 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). Features • Timer−Based Transient Power and Overload Protections with Auto−Recovery (Option B) or Latched (Option A) Operation • High−Voltage Current Source with DSS with Built−in Brown−out and Line Overvoltage Protections • Fixed−Frequency Current−Mode Operation with Built−in Ramp Compensation • Frequency Jittering for a Reduced EMI Signature • Adjustable Overpower Compensation • Latch−off Input for Severe Fault Conditions, with Direct Connection of an NTC for Overtemperature Protection (OTP) • Protection Against Winding Short−Circuit • Frequency Foldback transitioning into Soft−Skip 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 Soft−Start • Internal Thermal Shutdown with Hysteresis • These Devices are Pb−Free, Halogen Free/BFR Free and are RoHS Compliant* Typical Applications • ac−dc Adapters for Notebooks, LCD, and Printers • Offline Battery Chargers • Consumer Electronic Power Supplies • Auxiliary/Housekeeping Power Supplies *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. SOIC−7 CASE 751U MARKING DIAGRAM http://onsemi.com 37Xff ALYWX G 1 8 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 = Pb−Free Package See detailed ordering and shipping information in the package dimensions section on page 32 of this data sheet. ORDERING INFORMATION |
Similar Part No. - NCP1237 |
|
Similar Description - NCP1237 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |