RTL is an essential part of IC system design. How important is RTL design? Essentially, the logical functions of IC systems are implemented in RTL, so many IC projects are closely tied to RTL design. Today, let’s discuss how to excel in RTL design.
Generally, once the preparatory work and product requirements are determined, engineers can proceed with RTL design. To ensure project progress, the following steps will be taken:
1. First, define the structure of the design. Typically, an RTL design can be roughly divided into IOPad, clock generation circuits, reset circuits, JTAG circuits, cores, etc.
Of course, the chip division is related to the specific design. Choose the appropriate division method based on actual circumstances, rather than applying a one-size-fits-all approach.
2. Effective communication with other members of the project team is essential. Engage with marketing personnel to determine product functions; communicate with other designers to establish naming conventions, module divisions, and interfaces for each module. Effective communication is key to the success of a project.
3. Establish a unified directory structure for the project, where all members conduct their designs.
4. Implement unified version control.
5. Conduct reasonable module division. Consider the logical functions, design goals, and timing requirements, and try to group related modules together to reduce inter-module dependencies, facilitating subsequent synthesis and layout. Dividing by function ensures a clear structure, making it easier to assign tasks to different members.
6. Establish a unified verification platform. It is best for different members of the same project team to use a unified testing and verification framework, applying their own stimuli separately. If system design is completed before RTL design begins, the system design model can serve as a benchmark for RTL design verification. The testing platform should ideally be established early in the project.
7. Consider the debugging plan for the chip. After the first silicon return, debugging is needed. Given the large scale and complex functions of current IC systems, errors can easily occur, making the debugging plan crucial. A debugging plan should be considered early in the design process. To facilitate error localization, designers should test major functional modules separately. For example, in a communication chip, the analog section, digital signal processing section, and MAC section should be debuggable separately. In large designs, pins are always very valuable, and designers should carefully design the pin reuse plan, determining the functions of these pins during normal operation, debugging, and DFT. The pin allocation plan should be documented.
8. Provide design documentation. Unfortunately, this is often overlooked in many projects. People tend to wait until the project is finished to start writing design documents.
9. When writing each module, it is best to provide a block diagram; a picture is worth a thousand words.