The TOP271EG is an integrated Offline Switcher with EcoSmart™ Technology for highly efficient power supplies. TOPSwitch-JX incorporates a 725V power MOSFET and high-voltage switched current source, multi-mode PWM control, oscillator, fault protection and other control circuitry onto a monolithic device. It is an integrated switched mode power supply chip that converts a current at the control input to a duty cycle at the open drain output of a high-voltage power MOSFET. During normal operation the duty cycle of the power MOSFET decreases linearly with increasing CONTROL pin current. It features the high-voltage start-up, the cycle-by-cycle current limiting, loop compensation circuitry, auto-restart and thermal shutdown, the TOP264 incorporates many additional functions that reduce system cost, increase power supply performance and design flexibility. A patented high-voltage CMOS technology allows both the high-voltage power MOSFET and all the low voltage control circuitry.
Energy efficient over entire load range
Multi-mode PWM control maximizes efficiency at all loads
Accurate programmable current limit
Optimized line feed-forward for line ripple rejection
Frequency jittering reduces EMI filter
Fully integrated soft-start for minimum start-up stress
Simplifies meeting design derating requirements
User programmable for hysteretic/latching shutdown
Simple fast AC reset
Primary or secondary sensed
Line undervoltage detection prevents turn-OFF glitches
Line overvoltage shutdown extends line surge withstand
Accurate thermal shutdown with large hysteresis
Input pin for external current limit adjustment remote ON/OFF and device reset
Input pin for selecting switching frequency 132kHz if connected to SOURCE pin
Output MOSFET source connection for high-voltage power return