The TOPSwitch-II family is a three-terminal off-line PWM switch with features such as low cost, low component count, high efficiency, built-in auto-restart and current limiting. It can implement flyback, forward, boost or buck topology, and works with primary or opto feedback, stable in discontinuous or continuous conduction mode.
The document describes the TOPSwitch-II family of integrated circuits, which combine a power MOSFET, PWM controller, high-voltage startup circuit, loop compensation, and fault protection into a single three-terminal monolithic IC. These devices are designed for switched mode control systems in applications such as TVs, monitors, and audio amplifiers, offering efficiencies up to 90%.
| Power Range (100/115/230 VAC) | 100W to 150W |
|---|---|
| Power Range (85-265 VAC) | 50W to 90W |
| Maximum Efficiency | up to 90% |
| Nominal Oscillator Frequency | 100 kHz |
The CONTROL pin serves as an error amplifier and feedback current input for duty cycle control, while also providing internal bias current during normal operation.
The auto-restart circuit uses a divide-by-8 counter that prevents the output MOSFET from turning on again until eight discharge-charge cycles have elapsed, limiting power dissipation.