NCP1248: Fixed Frequency Current Mode Controller for Flyback Converters

The NCP1248 is a new fixed-frequency current-mode controller featuring the Dynamic Self-Supply. This 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 start-up, transients, latch, stand-by etc. This device contains a special HV detector which detect the application unplug from the AC input line and triggers the X2 discharge current. This HV structure allows the brown-out detection as well. It features a timer-based fault detection that ensures the detection of overload and an adjustable compensation to help keep the maximum power independent of the input voltage. Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an excellent candidate for the robust power supply designs. A dedicated Off mode allows to reach the extremely low no load input power consumption via “sleeping” whole device and thus minimize the power consumption of the control circuitry. This product is IEC60950 compliant. Please see the test report and certification in the Conformance report section below.

特性
  • Frequency foldback and skip mode
  • Timer-based overload protection with latched (A version) or auto-recovery (B version) operation
  • High-voltage startup with dynamic self supply
  • Integrated brown-out detection
  • Frequency Modulation
  • Adjustable overpower protection
  • Latch off input
优势
  • Optimized efficiency across the entire load range
  • Protection against overcurrent and short circuit
  • Simplifies the design of the auxiliary supply
  • Protects against any drops in line voltage
  • Softened EMI signature
  • Automatically adjusts the current limit depending on the line input voltage (high line or low line)
  • Protection against faults
应用
  • AC-DC Adapters
  • LCD TV power supplies
终端产品
  • Notebook Computers
数据表 (1)
Document TitleDocument ID/SizeRevisionRevision Date
Fixed Frequency Current Mode Controller for Flyback ConvertersNCP1248/D (1207kB)0Dec, 2014
封装图纸 (1)
Document TitleDocument ID/SizeRevision
SOIC 7 CASE OUTLINE751U (62.0kB)E
产品订购型号
产品状况Compliance封装MSL*容器预算价格 (1千个数量的单价)
NCP1248AD065R2GActivePb-free Halide freeSOIC-7751U1Tape and Reel2500$0.5
NCP1248AD100R2GActivePb-free Halide freeSOIC-7751U1Tape and Reel2500$0.5
订购产品技术参数
ProductTopologyControl Modefsw Typ (kHz)Stand-by ModeUVLO (V)Short Circuit ProtectionLatchSoft StartVCC Max (V)Drive Cap. (mA)
NCP1248AD065R2GStep-Up/Step-DownCurrent Mode65Yes8.9YesYesYes28500 / 800
NCP1248AD100R2GStep-Up/Step-DownCurrent Mode100Yes8.9YesYesYes28500 / 800
Fixed Frequency Current Mode Controller for Flyback Converters (1207kB) NCP1248
SOIC 7 CASE OUTLINE NCL30060