Onsemi NCP1027

Description

The NCP1027 offers a new solution targeting output power levelsfrom a few watts up to 15 W in a universal mains flyback application.Our proprietary high- voltage technology lets us include a powerMOSFET together with a startup current source, all directlyconnected to the bulk capacitor. To prevent lethal runaway in lowinput voltage conditions, an adjustable brown- out circuitry blocksthe activity until sufficient input level is reached.Current-mode operation together with an adjustable rampcompensation offers superior performance in universal mainsapplications. Furthermore, an Over Power Protection pin brings theability to precisely compensate all internal delays in high input voltageconditions and optimize the maximum output current capability.Protection wise, a timer detects an overload or a short- circuit andstops all operations, ensuring a safe auto- recovery, low duty cycle burstoperation. An integrated, auto- recovery, Overvoltage Protectionpermanently monitors the VCC level and temporarily shuts down thedriving pulses in case of an unexpected feedback loop runaway.Finally, a great RDS(on) figure makes the circuit an excellent choicefor standby/auxiliary offline power supplies or applications requiringhigher output power levels.

Features

• Built-in 700 V MOSFET with Typical RDS(on) of 5.8 , TJ = 25°C
• Current-Mode Fixed Frequency Operation: 65 kHz and 100 kHz
• Fixed Peak Current of 800 mA
• Skip-Cycle Operation at Low Peak Currents
• Internal Current Source for Clean and Lossless Startup Sequence
• Auto-Recovery Output Short Circuit Protection with Timer-BasedDetection
• Auto-Recovery Overvoltage Protection with Auxiliary WindingOperation
• Programmable Brown-Out Input for Low Input Voltage Detection
• Programmable Over Power Protection
• Input to Permanently Latchoff the Part
• Internal Frequency Jittering for Improved EMI Signature
• Extended Duty Cycle Operation to 80% Typical
• No-Load Input Standby Power of 85 mW @ 265 Vac
• 500 mW Loaded, Input Power of 715 mW @ 230 Vac
• These are Pb-Free Devices

Typical applications

• Auxiliary/Standby Power Supplies for ATX and TVS Power Supplies
• Medium Power AC-DC Adapters for Chargers

More information

• Datasheet
• IC product information