If you’re doing your own PCB layout, being prepared may just help you organize and remember important design details. However, if the design is sent to someone else for layout, this lack of preparation can cause major problems in completing the design.

Let’s take a look at some things to consider in the schematic to make it easier to switch PCB layouts.

How to convert PCB layout? Rule number one: Clean documentation？

Circuit design may come from scribbled notes on paper, or schematics drawn hastily on a chalkboard, but of course these are not properly documented. Many medical institutions are now forcing doctors to electronically file prescriptions instead of writing them down with pen and paper, so patients can read them easily.

Just as it is important to be able to read prescriptions correctly, so is reading detailed information and instructions from schematics. Do yourself a favor and take the time to make sure the schematics are legible.

Here are some tips on how to do it correctly:

Use grids to align symbols, draw lines, and organize text.

The text font and line width should be large enough to be easy to read, but not so large that it confuses the schematic.

Don’t crowd symbols and text together; leave some space for them so they can be read accurately.

Write schematics with logical flow that makes sense. There is no need for components to be stuck in a region; they can be blocked as long as they really don’t belong there.

If you can create more readable documents, you don’t have to worry about using other pages in your schematic.

If you give yourself enough time to create easy-to-use documents, you’ll get a lot of benefit from that extra effort during the layout process.

Library parts are essential for converting PCB layouts

Another important part of successfully converting schematics into PCB layouts is ensuring that library parts are up to date and correct. What the symbol represents must be correct. This includes pushpins, text, shapes, and attributes. Sometimes people use existing symbols as templates to build new ones, then ignore adding, deleting, or modifying parts of the original message. Better yet, there can be a lot of confusion when the part number on the schematic drawing does not match the part number reported in the report. The worst case scenario is that the symbolic information is completely wrong and leads to a connection error in the schematic or downstream tool, such as the emulator.

When building a new symbol for your design, be sure to include all relevant component information as well. This will include the layout tool’s physical footprint name, company part number, supplier part number, cost information, and simulation data. Every company has its own standards for what should or should not be included in a library section, but having too much information is better than having too little. When you’re done, make sure you populate the new part with the appropriate component library and that the parts on the schematic are updated to reference the correct library.

Detailed and complete schematic information is important

Just as there is not much information in library parts, the same applies to schematics. Be careful not to add so much data that the schematic becomes difficult to read, but add enough information to help downstream with layout, testing, and rework. Here are some examples of relevant information:

Identification of schematic functional areas (” power supply “, “fan control”, etc.).

Test the position of power supply, grounding or specific signals.

Placement of fixed components such as connectors and plugs.

Components are grouped to identify high-speed or sensitive placement areas.

Sensitive circuits that may require special attention, such as RF shielding.

Hot areas of concern.

High-speed circuit requirements, such as measured wiring length or controlled impedance wiring.

Differential pair.

In addition to the functional information listed above, don’t forget to include all the general schematic document data. This will include items in the title bar, such as company name, part number, revision, board name, date, and copyright information. By making sure you have enough information on the schematic and as much data as possible, but not too burdensome, it helps to ensure a successful conversion of the schematic to the PCB layout.