TOPSwitch-GX uses the same proven topology as TOPSwitch, cost effectively integrating the high voltage power MOSFET, PWM control, fault protection and other control circuitry onto a single CMOS chip. Many new functions are integrated to reduce system cost and improve design flexibility, performance and energy efficiency. Depending on package type, the TOPSwitch-GX family has either 1 or 3 additional pins over the standard DRAIN, SOURCE and CONTROL terminals allowing the following functions: line sensing (OV/UV, line feedforward/DC max reduction), accurate externally set current limit, remote on/off, and synchronization to an external lower frequency and frequency selection (132 kHz/66 kHz).