Synchronous rectifier MOSFET driver substantially reduces power adapter heat

Using conventional methods with a rectifier on the secondary side of power adapter produces more heat. The heat generated, especially on high wattage power adapters, is even worse. An innovative high-speed controller, called synchronous rectifier MOSFET driver (or Driver), is designed to drive a power MOSFET in high current high frequency fly-back converters. The circuit does not require any ties to the primary side and derives its operating power directly from the secondary side. The circuit functions are structured by anticipating transformer output transition then turns the power MOSFET on or off before the transitions of the transformer to minimize body drain diode conduction and reduce associated heat losses. The advantages of using this solution that will be discussed are high efficiency, safe operation for lower operating temperatures, and ease of design and manufacturing.