DC-DC EI35的磁芯和IRF640功率能达到要求么?

采用uc3845 EI35的磁芯+IRF640(200V 16A),做12v-24v直流输入 输出3路 每路5V 3~4A,要求隔离 不知道功率上面有没有问题?是不是要做成正激才能满足?
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