> For the complete documentation index, see [llms.txt](https://docs.quilter.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.quilter.ai/physics-rule-checks-prcs/overview.md). # Overview Overview of Physics Rule Checks (PRCs) applied by Quilter to validate user-defined physics constraints. Physics rule checks (PRCs) validate candidates by ensuring that the critical parameters for each physics constraint are satisfied. Quilter produces PRC reports for every layout candidate it examines. During Circuit Comprehension, Quilter reads your schematic and input board file to automatically detect [Physics Constraints](/physics-constraints/overview.md) that capture the core physics concerns in your design. Quilter generates a set of PRCs for each identified constraint as a way to evaluate the implementation of that constraint in the layout candidates that it generates. For example, [Differential Pairs](/physics-constraints/differential-pairs.md)are checked to validate appropriate length matching, tightly coupled spacing, and ground plane overlap. Continue reading for a complete overview of supported Physics Rule Checks and the associated physics constraints that they support. ### PRCs by Constraint Type

Physics Constraint	Applied PRCs
Power Nets	Overheated Length
Timing-sensitive Signals	Coming soon
Single-ended Impedance Control	Invalid Width Span Ground Plane Overlap
Differential Pairs	Ground Plane Overlap Uncoupled Spacing Length Mismatch
Bypass Capacitors	Pin Distance Trace Path Length Layer Switch Count Ground Plane Overlap
Crystal Oscillators	Pin Distance Trace Path Length Layer Switch Count Ground Plane Overlap
Switching Converters	Pin Distance Trace Path Length Layer Switch Count Ground Plane Overlap

### PRC Results

Example PRC result for a Bypass Capacitor constraint

During the review step, you will see passing and failing PRCs alongside candidates, allowing you to be confident that the design will work as expected. For failing PRCs, the documentation for each PRC provides more insight into the listed error. For more information on interpreting PRC results, see [Reviewing PRCs](/reviewing-prcs.md). --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.quilter.ai/physics-rule-checks-prcs/overview.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.