LINEAR TECHNOLOGY DC1961A 演示电路板, LT8309, 反激式转换器
The is a Demonstration Board for LT8309 a secondary synchronous driver in an isolated no-optocoupler flyback converter. It regulates a 12V, 5A output from a 36 to 72V input source. Output regulation is handled on the primary side by the LT3748, a boundary conduction mode flyback controller which senses output voltage directly from the primary. On the board the LT8309 is biased from the rectified drain voltage node of secondary side synchronous MOSFET, not directly connecting to output voltage. This configuration allows the synchronous MOSFET to remain conducting at all times, even when output is shorted to ground, so as to provide a very robust short circuit performance. The Performance Summary table summarizes the performance of the demo board at room temperature. For thermally critical applications, proper amount of air flow can help to reduce power components" temperature rise, therefore greatly improving circuit reliability.