各位TI大神们,我是一名在校研究生,想用UCC28251做一款全桥模块电源,看过该芯片的手册后,有一问题就是当轻载时电感电流断续的情况下,同步整流管仍然开通着,那么会有倒灌电流流入整流管致其烧坏,请问贵公司在这方面是怎么考虑的。谢谢!
Wu JW:
你可以外加一些线路,判断负载情况。
如用电流检测线路,检测输出电流,当输出电流较小时,让同步MOS管不工作,使其体二极管(或MOS管并联一个整流二极管)来导通工作。
Jimmy Zhou95:
Hi, The SRs can carry current in both directions so the output inductor current will not go discontinuous. The SRs won't try to interrupt a negative going current (from drain to source) so there should be no spike. I'd suggest that you download and run the TINA-TI reference design for the UCC28251 (its on the 'Tools and Software' tab and see how it behaves. Regards