Clocking and PLL User Guide: Agilex™ 5 FPGAs and SoCs

ID 813671
Date 4/01/2024
Public
Document Table of Contents

4.2. Clock Control IP Core Parameters

Table 5.   Clock Control IP Core Parameters for Agilex™ 5 Devices
Parameter Value Description
Number of Clock Inputs 1, 2, or 4

Specify the number of input clock sources for the clock control block. You can specify up to four clock inputs.

Clock multiplexing in Agilex™ 5 devices is implemented using soft logic in the core.

Ensure glitch free clock switchover On or Off

Turn on this option to implement a glitch-free switchover in soft logic when you use multiple clock inputs. You must ensure the currently selected clock is running before switching to another source.

If the selected clock is not running, you cannot switch to the new clock source using the glitch-free switchover implementation.

The clkselect port is initially configured as 00 by default. To activate the clkselect ports and drive the clock network, a clock signal must be provided to inclk0x.

Turning off this option implements a simple multiplexer logic. For more information on optimal clock multiplexing design, refer to Clock Multiplexing in the Quartus® Prime Pro Edition: Design Recommendations.

Clock Enable On or Off Turn on this option if you want to gate your clock output with an enable signal. This option disables the option to use clock division.
Clock Enable Type Root Level or Distributed Sector Level Select the clock gates located in the periphery or the gates located in the sector. For more information about the clock gates, refer to the Clock Gating section.
Enable Register Mode Negative Latch or None Specify if the enable signal should be latched.
Clock Divider On or Off Turn on this option if you want to use the clock division block in the periphery.

This option disables the option to use clock enable.

Clock Divider Output Ports Divide 1x, Divide 1x and 2x, or Divide 1x, 2x and 4x Specify the combination of passing your clock through, dividing your clock by 2, or dividing your clock by 4.