你好!!
ls200 fpgep3ca中 pllout时钟输出引脚中说Optional negative terminal for external clock outputs from PLL[1..4]. These pins can only use the
differential I/O standard if it is being fed by a PLL output
什么意思,时钟输出引脚只能做差分输出吗?
我用单端做时钟输出不行吗?一般的都是用做单端输出的,怎么这个必须用差分?谢谢 |