BUFGMUX_CTRL with a Clock Enable

UltraScale Architecture Clocking Resources User Guide (UG572)

Document ID
UG572
Release Date
2023-02-01
Revision
1.10.2 English

A BUFGMUX_CTRL with a clock enable BUFGCTRL configuration allows you to choose between the incoming clock inputs. If needed, the clock enable is used to disable the output. This Figure illustrates the BUFGCTRL usage design example and This Figure shows the timing diagram.

Figure 2-16: BUFGMUX_CTRL with a CE and BUFGCTRL

X-Ref Target - Figure 2-16

X16677-bufgmuxctrl-ce-bufgctrl-block.jpg
Figure 2-17: BUFGMUX_CTRL with a CE Timing Diagram

X-Ref Target - Figure 2-17

X16678-bufgmuxctrl-ce-timing.jpg

In This Figure :

At time event 1, output O uses input I0.

Before time event 2, S is asserted High.

At time TBCCKO_O, after time event 2, output O uses input I1. This occurs after a High-to-Low transition of I0 followed by a High-to-Low transition of I1 is completed.

At time TBCCCK_CE, before time event 3, CE is asserted Low. To avoid any output clock glitches, the clock output is switched Low and kept at Low until after a High-to-Low transition of I1 is completed.