NCP1937xxG AWLYWW NCP1937 Combination Power Factor Correction and Quasi- Resonant Flyback Controllers for Adapters www.onsemi.com This combination IC integrates power factor correction (PFC) and quasiresonant flyback functionality necessary to implement a MARKING DIAGRAM compact and highly efficient Switched Mode Power Supply for an 120 adapter application. HV/X2 PFBHV The PFC stage exhibits nearunity power factor while operating in a BO/X2 PFBLV Critical Conduction Mode (CrM) with a maximum frequency clamp. GND PControl PCS/PZCD The circuit incorporates all the features necessary for building a robust SOIC20 PONOFF PDRV and compact PFC stage while minimizing the number of external Narrow Body QCT QDRV CASE 751BS Fault QCS components. PSTimer VCC The quasiresonant currentmode flyback stage features a QFB QZCD proprietary valleylockout circuitry, ensuring stable valley switching. th NCP1937 = Specific Device Code This system works down to the 4 valley and toggles to a frequency xx = A1, A2, A3, B1, B2, B3, C1, C4 or C61 th foldback mode with a minimum frequency clamp beyond the 4 A = Assembly Location valley to eliminate audible noise. Skip mode operation allows WL = Wafer Lot excellent efficiency in light load conditions while consuming very low YY = Year WW = Work Week standby power consumption. G = PbFree Package Common General Features Wide V Range from 9 V to 30 V with Builtin Overvoltage CC Protection ORDERING INFORMATION See detailed ordering and shipping information on page 5 of HighVoltage Startup Circuit and Active Input Filter Capacitor this data sheet. Discharge Circuitry for Reduced Standby Power Integrated HighVoltage BrownOut Detector Integrated HighVoltage Switch Disconnects PFC Feedback Resistor Divider to Reduce Standby Power Fault Input for Severe Fault Conditions, NTC FeedForward for Improved Operation across Line and Compatible (Latch and AutoRecovery Options) Load 0.5 A / 0.8 A Source / Sink Gate Drivers Adjustable PFC Disable Threshold Based on Output Power Internal Temperature Shutdown Power Savings Mode Reduces Supply Current QR Flyback Controller Features Consumption to 70 A Enabling Very Low Input Power Valley Switching Operation with ValleyLockout for Applications NoiseFree Operation Frequency Foldback with Minimum Frequency Clamp PFC Controller Features for Highest Performance in Standby Mode Critical Conduction Mode with Constant On Time Minimum Frequency Clamp Eliminates Audible Noise Control (Voltage Mode) and Maximum Frequency Clamp TimerBased Overload Protection (Latched or Accurate Overvoltage Protection AutoRecovery options) BiLevel LineDependent Output Voltage Adjustable Overpower Protection Fast Line / Load Transient Compensation Winding and Output Diode ShortCircuit Protection Boost Diode ShortCircuit Protection 4 ms SoftStart Timer Semiconductor Components Industries, LLC, 2015 1 Publication Order Number: June, 2015 Rev. 4 NCP1937/DN NCP1937 Figure 1. Typical Application Circuit www.onsemi.com 2 L PDRV N L VZCD VCC (Aux) HV/X2 PFBHV PCS/PZCD PFBLV BO/X2 GND PControl PCS/PZCD PCS/PZCD PONOFF PDRV PDRV QCT QDRV QCS Fault QCS PSTimer VCC VCC QFB QZCD QCS NCP1937 VZCD VPSTimer PSM Control