1. Use Good Naming Conventions
When considering file names for the schematic, consider using a naming convention that includes the revision number or letter to assist in configuration management. Before starting any major new sections of the design, save the file with a revision ‘dot’ numeric or date code (such as AmpProject_revA_1 or AmpProject_revA_20100822). In this way, previous schematic edits or simulations can be compared as they are updated. Information such as the customer’s name, part number and model name among other things can be used within the schematic name.
This information should also be included in the title block of the schematic. As shown in Figure 1, it is also a good practice to create a project folder structure with an archive folder to store older revisions of the schematic. Additional folders may be created such as components for saving technical data sheets, simulation to save simulation data and layout to save any specific PCB layout files.
2. Document Design Requirements
Be sure all customer requirements have been included in the schematic and associated documentation. For example, Multisim has a Comments and a Circuit Description Box for documentation purposes. Consider placing critical information directly in the schematic as text labels, allowing this information to be easily displayed or printed in proportion to the symbol content. Also, include information such as performance criteria, special signal or ground requirements, and any custom part information directly in the schematic so that this information can be visually seen when working within the simulation and layout stages.
3. Use Simulation
Use simulation to test the circuit for functionality and performance requirements. When special simulation-only symbols are used for experimental simulation purposes, be sure to save a special revision of the circuit to tag it as having specific simulation capabilities. Alternatively, the portion of the design needing simulation can be directly copied and pasted into a new schematic capture sheet. When allocating the amount of time to spend on simulation, consider the benefits of performing simulation to meet initial circuit requirements and the benefits obtained in validating or troubleshooting design performance while testing the initial prototypes. Moreover, interactive simulation is an effective way of performing interactive debug and troubleshooting while comparing live measurements during initial prototype testing.
4. Build Up a User-Defined Collection of Parts
Although parts can always be reliably chosen from a Master database, consider selecting parts chosen only from your own User or Corporate databases. When using a component from a Master database, consider copying it to your own Corporate or User database and adding any custom information as desired. This way a personalized collection of familiar parts can be created through this process. Also any part modifications can easily be updated through the user and corporate databases. In the case where the Master database is updated, any custom part deviations or specific vendor information that has been added can be used for other projects if they reside in the User or Corporate databases.
Tip: Consider backing up your databases periodically to the archive folder.
5. Add Vendor Information for Components
When searching for components, be sure all components have ordering information in the user fields (vendor name, vendor part number, etc). If properly populated, the user field data can be generated in the Bill of Materials Report to facilitate the ordering process. In some cases the component data can be exported to a file and can be emailed to a vendor as part of the ordering process. Before committing components to the PCB design, ensure the parts have appropriate quantities, availabilities and appropriate prices from the selected vendors.
