Description
The STR-X6729 is a quasi-resonant topology IC designed for SMPS applications. It shows lower EMI noise characteristics than conventional PWM solutions, especially at greater than 2 MHz. It also provides a soft-switching mode to turn on the internal MOSFET at close to zero voltage (VDS bottom point) by use of the resonant characteristic of primary inductance and a resonant capacitor.

Features and Benefits
▪ Quasi-resonant topology IC => Low EMI noise and soft switching
▪ Bottom-skip mode => Improved system efficiency over the entire output load by avoiding increase of switching frequency
▪ Standby mode => Lowers input power at very light output load condition
▪ Avalanche-guaranteed MOSFET => Improves system-level reliability and does not require VDSS derating
▪ 450 VDSS / 0.189 Ω RDS(on)
▪ Various protections => Improved system-level reliability
   ▫ Pulse-by-pulse drain overcurrent limiting
   ▫ Overvoltage Protection (bias winding voltage sensing), with latch
   ▫ Overload Protection with latch
   ▫ Maximum on-time limit

Applications include the following:
▪ Set Top Box
▪ LCD PC monitor, LCD TV
▪ Printer, Scanner
▪ SMPS power supplies