Intel® MAX® 10 FPGA – AN 501: Pulse Width Modulation Design Example

The duty cycle and average DC value of the signal can be varied. PWM provides a powerful method for controlling analog circuits with the help of an output from a digital system. A few applications include:

• Telecommunication: Data corresponding to particular pulse widths is encoded at one end and decoded at the other end.
• Voltage regulation: The output voltage in a voltage regulator system can be controlled to a desired level by varying the duty cycle.
• Power delivery: You can vary the average power delivered, which is a function of the modulated duty cycle.
• Audio effects and amplification: Used in sound synthesis.

You can visually observe PWM with intensity variation in LEDs, which are known for their fast switching speeds. Intensity variation in the LED is an outcome of the variation in average DC voltage and the current through the LED due to PWM.

Prepare the design template in the Quartus Prime software GUI (version 14.1 and later)

Note: After downloading the design example, you must prepare the design template. The file you downloaded is of the form of a <project>.par file which contains a compressed version of your design files (similar to a .qar file) and metadata describing the project. The combination of this information is what constitutes a <project>.par file. In releases 16.0 or newer, you can simply double click on the <project>.par file and Quartus will launch that project.

The second means to bring up the project template is through the New Project Wizard (File -> New Project Wizard). After entering the project name and folder on the first panel, the second panel will ask you to specify an empty project or project template. Select project template. You will see a list of Design Templates projects that you have loaded prior as well as various "Baseline Pinout Designs" that contain the pinout and settings for a variety of development kits. If you don't see your design template in the list, click on the link that states install the Design Templates circled below:

Browse to the <project>.par file you downloaded, click next, followed by Finish, and your design template will be installed and displayed in the Project Navigator pane in Quartus.

Note: When a design is stored in the Design Store as a design template, it has been previously regression tested against the stated version of Quartus software. The regression ensures the design template passes analysis/synthesis/fitting/assembly steps in the Quartus design flow.

Prepare the design template in the Quartus Prime software command-line

At the command-line, type the following command:

quartus_sh --platform_install -package <project directory>/<project>.par

Once the process completes, then type:

quartus_sh --platform -name <project>

Note:

* ACDS Version: 16.1.0 Standard