FLL+不接外部低频，会怎样？

哦，就是说不推荐这么使用。

从4xx的特性来说，所有的4xx芯片都带LCD Driver，只要用了LCD，就需要一个低频时钟来做LCD刷新频率的resource。所以，肯定板上会有一颗低频晶振，否则也就不会选择4xx了吧

camus

您好！

在User's Guide中有这么一段话

“During a LFXT1crystal failure, no ACLK signal is generated and the FLL+ continues to count down to

zero in an attempt to lock ACLK and MCLK/(D×[N+1]). The DCO tap moves to the lowest position (SCFI1.7 to SCFI1.3 are cleared) and the DCOF is set. A DCOF is also generated if the N-multiplier value is set too high for the selected DCO frequency range resulting the DCO tap to move to the highest position (SCFI1.7 to SCFI1.3 are set). The DCOF is cleared automatically if the DCO tap is not in the lowest or the highest positions.”

还有，经常见您在论坛上出现，不知道您43现在基于在做什么项目呢？

当然需要一个低频时钟来做LCD刷新频率的resource，但不一定要外部低频，我们还有VLO.

我是一个初学者，用4132搭外围电路，做触摸按键。

To 鸵鸟蝈蝈

“During a LFXT1crystal failure, no ACLK signal is generated ”.这句话不对，我拿掉了32768，选择VLO输出ACLK，ACLK依然有效呀，做过实验的。