TOP243PN Off-line Switcher IC

TOPSwitch-GX family introduced by Power Integrations uses the same proven topology as TOPSwitch. This switcher IC comprises of high voltage power MOSFET, PWM control, fault protection, and other control circuitry integrated into a single CMOS chip. Various new functions are employed in this IC to reduce system cost and improve design flexibility, performance and energy efficiency.

Based on package type, either 1 or 3 additional pins over the TOPSwitch standard DRAIN, SOURCE and CONTROL terminals allow the certain features such as line sensing (OV/UV, line feed-forward/DCMAX reduction), accurate externally set current limit, remote ON/OFF. Moreover, it also offers a synchronization to an external lower frequency, and frequency selection (132 kHz/66 kHz). All package types offers the subsequent transparent features such as Soft-start, 132 kHz switching frequency (automatically reduced at light load), frequency jittering for lower EMI. And also provides wider DCMAX, hysteretic thermal shutdown, and bigger creepage packages. Moreover, all critical parameters ( current limit, frequency, PWM gain) provides tighter temperature and absolute tolerances to simplify design and optimize system cost.

These IC functions as  a switched-mode power supply chip that converts a current at control input to a duty cycle at the open-drain output of high voltage power MOSFET. During normal functioning of the IC, the duty cycle of the power MOSFET reduces linearly with increase in CONTROL pin current.

Moreover, the TOPSwitch IC features, high voltage start-up, the cycle-by-cycle current limiting, loop compensation circuitry, auto-restart, thermal shutdown. And also the TOPSwitch-GX comprises of wide range of additional features that minimize system cost, increase power supply performance and style flexibility. A patented high voltage CMOS technology allows both the high voltage power MOSFET and every one the low voltage control circuitry to affordably integrated onto one monolithic chip.