Altera ALTCLKCTRL Megafunction User Guide

About this manual

The Clock Control Block (ALTCLKCTRL) megafunction is a clock control function provided by the Quartus II MegaWizard Plug-In Manager. It allows users to easily configure clock control blocks in supported Altera devices to manage clock distribution and power consumption.

Key applications include dynamic clock source selection, where the user can switch between different clock inputs to drive the global clock network, and dynamic power-down, which enables internal logic to power down a clock network to reduce overall device power consumption. The guide details parameter settings via the MegaWizard Plug-In Manager and the Command Line Interface.

What's inside

• About this Megafunction
• Parameter Settings
• Functional Description
• Global Clock Control Block
• Regional Clock Control Block
• External PLL Output Clock Control Block
• Clock Enable Signals
• Connectivity Restrictions
• Design Example
• Functional Simulation

Specifications

Frequently asked questions

How does the dynamic power-down feature work?

It allows internal logic to power-down the clock network, which stops logic toggling and reduces overall power consumption.

Which device families support the ALTCLKCTRL megafunction?

It is available for Arria, Cyclone, HardCopy, and Stratix device series.