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What is a PCB footprint courtyard?

A PCB footprint courtyard is a defined placement envelope around a component footprint. It helps the layout and assembly teams reserve the space a component needs. The envelope normally relates to the component body, terminals and land pattern, with an additional allowance selected from the applicable library convention and assembly requirements.

Courtyard, copper clearance, solder-mask opening and silkscreen outline are different design objects. A courtyard does not automatically prohibit every trace beneath a component, establish high-voltage insulation distances or guarantee room for a rework nozzle. Those requirements need their own rules. The value of the courtyard is that it makes a placement assumption visible and checkable instead of leaving it to visual judgment.

This page addresses footprint envelopes and library review. Design for assembly owns the wider board-level task: placement, soldering, inspection, test access and manufacturing documents. Keep that distinction when a spacing problem appears. An overlap may be a library error, a deliberate mechanical arrangement or a real assembly restriction; each needs a different response.

Separate the five outlines before measuring clearance

Start with the exact component drawing and intended land pattern. A body can be smaller than the overall lead span or pad extent. Conversely, a tall connector may require a large mating or extraction region that is not represented by its solder pads. Measuring only the molded body gives an incomplete answer for both cases.

Keep the library鈥檚 dimensional convention explicit. Some published library conventions calculate their body-based courtyard allowance from nominal dimensions. A project may additionally review maximum component dimensions and assembly tolerances. Do not silently mix these conventions or present one offset as a universal physical guarantee. Record which outline and dimension basis were used.

Explore the envelope and the gap between two parts

The worksheet compares two axis-aligned rectangular envelopes on the same board side and at the same Y position. Enter each envelope鈥檚 width, the chosen allowance at either side and the X center-to-center distance. It reports the resulting courtyard gap or overlap. The drawing is a planning illustration; it does not import the board or perform a full collision check.

For two envelope widths A and B, the required center spacing in this simplified arrangement is (A + B)/2 + allowance A + allowance B. If A is 10 mm, B is 6 mm and the respective allowances are 0.25 and 0.5 mm, the required spacing is 8.75 mm. An entered spacing of 8.6 mm gives a 0.15 mm courtyard overlap. Those chosen allowances demonstrate the calculation rather than prescribe an assembly limit.

The sign of that result is useful: a negative value means the modeled envelopes overlap in X. It does not prove the physical parts collide, and a positive result does not prove there is enough soldering, inspection or repair access. Rotation, irregular shapes, different Y positions, underside geometry and enclosure constraints require the actual CAD model and relevant process review.

Apply library conventions with their actual scope

The identifies the standards topic relevant to surface-mount land-pattern design. Use the applicable authorized publication and project requirements for the actual design decision. A courtyard drawn using a CAD library convention is not, by itself, evidence of IPC compliance or an approved assembly process.

defines the courtyard layers, closed-outline requirements and category-specific allowances for its library. It also calls out additional mating clearance for connectors. These are useful, explicit library rules; they should not be rewritten as a universal 吃瓜tv process capability or copied without considering the component category.

In KiCad, front and back courtyard layers distinguish the board side. Check that the shape is closed and that it represents the intended footprint rather than an outdated component revision. A courtyard on the wrong side or a missing segment can undermine the check even when the footprint looks tidy in a screenshot. Keep the library revision in the release record.

explains that rule behavior depends on component-boundary and 3D settings. Know what geometry the rule is checking. A named mechanical layer is not necessarily equivalent to the configured Courtyard layer type, and a 2D envelope check differs from a 3D body check.

Reserve room for the operation, not only the package

A placement machine must place the part, but the board may later need optical inspection, cleaning, probing or repair. These tasks do not always require the same space. A small passive beside a tall connector may be geometrically separate yet difficult to inspect or replace. Discuss the relevant operations before reducing allowances to achieve a smaller board outline.

Connector access is directional. A plug may approach horizontally, a latch may need finger or tool access, and a cable may have a minimum bend requirement. Keep this mating envelope separate from the soldering footprint when that makes the constraint clearer. Show it on the mechanical drawing and inspect it in the intended enclosure, not just on an isolated PCB view.

Thermal and electrical separation deserve their own review. Two courtyards touching does not tell you whether a hot component overheats its neighbor, or whether a conductor meets a required insulation distance. Likewise, an empty courtyard region can still contain a sensitive antenna or sensor field. Use explicit rules for those functions instead of expanding a courtyard until it ambiguously represents every requirement.

Three situations that need different decisions

A fine-pitch IC beside small passives. First verify the IC land pattern and passive envelope. Then consider solder deposition, component placement and inspection access. If the clearance is tight, ask whether the neighboring part height affects the intended process. Moving a silkscreen line does not solve an actual component-spacing restriction.

A connector extending beyond the board edge. The body may intentionally overhang. Check the board outline, connector seating reference, support and mating envelope together. The correct answer can be an approved, documented exception for that mechanical arrangement, not a blanket rule disabling component-clearance checks everywhere.

A shield enclosing a populated region. A shield鈥檚 perimeter, clip positions and assembly sequence affect component access. Parts may fit inside the final enclosure but obstruct the operation used to install or remove it. Model the required work area and identify which checks occur before closure. Keep the assembly drawing consistent with the CAD restrictions.

The assembled-board photograph illustrates why height and access matter alongside the top-view footprint. It is a placement reference, not evidence that a particular courtyard offset has been qualified. A meaningful review identifies the actual part pair and operation instead of applying a blanket gap to every component in the photograph.

Review the footprint library before freezing placement

Check the component manufacturer, full ordering code and package drawing revision. Compare pin numbering, orientation, body and terminal dimensions with the symbol and footprint. Confirm whether a recommended land pattern exists and whether the library uses that pattern or a documented alternative. Similar package names can conceal different terminal geometries.

Run the intended electrical and placement checks, then examine exceptions individually. A clean rule report has value only when the rules and geometry are appropriate. Do not remove all courtyard outlines to make violations disappear. Correct the library, move the component, change the mechanical design or document a justified exception with the assembly team.

For solder deposition questions, move to the PCB stencil guide rather than treating the courtyard as a paste-aperture rule. For the larger release, the assembly file checklist helps align placement data, BOM and drawings. These are natural next steps because an accurate envelope still needs a consistent manufacturing package.

Make an assembly-spacing enquiry easy to answer

Send the board revision, the two or more component references involved, exact part numbers, a dimensioned layout excerpt and a view showing relevant heights. State the concern: placement, reflow, inspection, cleaning, rework, mating or test. Include the selected courtyard convention and any deliberate exceptions. This gives the reviewer a specific question instead of a screenshot with an unexplained red marker.

If the board is dense, ask for review before completing every route. A modest placement change is usually easier while the design is still flexible. If placement is fixed by a connector or enclosure, identify that constraint so the review can consider process options and their implications. A local overlap may be solvable, but it should not be described as approved until the relevant process owner has assessed it.

Use PCB Assembly for the manufacturing scope and quote request. You can contact 吃瓜tv directly with your files; the worksheet is optional. Its text brief can be attached manually to preserve the entered assumptions. It does not transfer dimensions into the contact form or certify the assembly clearances.

PCB courtyard questions