LNK364PN

LinkSwitch-XT incorporates a 700 V power MOSFET, oscillator, simple ON/OFF control scheme, a high-voltage switched current source, frequency jittering, cycle-by-cycle current limit and thermal shutdown circuitry onto a monolithic IC. The startup and operating power are derived directly from the DRAIN pin, eliminating the need for a bias winding and associated circuitry. LinkSwitch-XT combines a high-voltage power MOSFET switch with a power supply controller in one device. Unlike conventional PWM (pulse width modulator) controllers, a simple ON/OFF control regulates the output voltage. The controller consists of an oscillator, feedback (sense and logic) circuit, 5.8 V regulator, BYPASS pin undervoltage circuit, over-temperature protection, frequency jittering, current limit circuit, and leading edge blanking integrated with a 700 V power MOSFET. The LinkSwitch-XT incorporates additional circuitry for auto-restart.

Applications

• Chargers/adapters for cell/cordless phones, PDAs, digital cameras, MP3/portable audio players, and shavers
• Supplies for appliances, industrial systems, and metering

Key features

• Optimized for Lowest System Cost
• Proprietary IC trimming and transformer construction techniques enable Clampless designs with LNK362 for lower system cost, component count and higher efficiency
• Fully integrated auto-restart for short circuit and open loop protection
• Self-biased supply – saves transformer auxiliary winding and associated bias supply components
• Frequency jittering greatly reduces EMI
• Meets HV creepage requirements between DRAIN and all other pins both on the PCB and at the package
• Lowest component count switcher solution
• Features Superior to Linear/RCC
• Accurate hysteretic thermal shutdown protection – automatic recovery improves field reliability
• Universal input range allows worldwide operation
• Simple ON/OFF control, no loop compensation needed
• Eliminates bias winding – simpler, lower cost transformer
• Very low component count – higher reliability and single side printed circuit board
• Auto-restart reduces delivered power by 95% during short circuit and open loop fault conditions
• High bandwidth provides fast turn-on with no overshoot and excellent transient load response
• EcoSmart– Extremely Energy-Efficient
• Easily meets all global energy efficiency regulations with no added components
• No-load consumption < 300 mW without bias winding at 265 VAC input (< 50 mW with bias winding)
• ON/OFF control provides constant efficiency to very light loads – ideal for mandatory CEC regulations