Open Flux now, switch Copilot to “Next-gen” and see how it handles your next design challenge. The sooner you try it, the more your feedback can shape the next leap in AI-powered hardware design.
This post explains key signal integrity issues like crosstalk and reflections in PCBs and offers simple layout tips to avoid them. A free guide is included.
You followed the datasheet, double-checked the footprints, and kept your traces clean. But the moment your board hits production, there’s noise on the lines, your timing margins collapse, or worse: the board doesn’t pass compliance.
This is what Signal and Power Integrity (SI/PI) is all about, and why it’s critical even for everyday designs.
Signal integrity issues fall into three buckets:
If you’re using fast clocks, long runs, or high-speed I/O—even on a two-layer board—these issues can bite.
Crosstalk happens when traces run too close in parallel. The energy from one net bleeds into the other, distorting waveforms and injecting unpredictable noise.
You’ll see false triggers or glitches in digital nets, unexpected ripple in analog sections and most of the times -- EMI issues in test.
Want a shortcut? If your trace spacing is less than 3× the width, and they run in parallel for more than a few centimeters, you probably have crosstalk.
You don’t need a PhD or 8-layer board to fix this. Try these:
Board materials, stack-up, impedance, and even your decoupling caps play a role.
If your stack-up lacks solid return planes, or your dielectric isn’t up to spec, no amount of “good routing” will save you.
This is why we put together a complete guide that breaks down:
With checklists, diagrams, and cheat sheets to design boards that work the first time, for FREE.
{{download-high-speed-guide}}
Flux Copilot’s new AI-powered part search makes finding and placing components faster and easier using natural language. It eliminates tool-switching and datasheet overload. This streamlines your PCB design workflow.
As fellow hardware designers, we know how disruptive this process can be. That’s why we’ve redesigned part search in Flux Copilot using advanced AI techniques, so you can stay focused on your design, not the scavenger hunt. Whether you're early in your journey or deep into system architecture, this upgrade makes intelligent part discovery accessible and reliable.
If you're new to PCB design, just figuring out what components to use can feel overwhelming. You might not know the terminology, part families, or what trade-offs actually matter. The goal of Copilot is to give you answers, not more decisions.
You don’t need to know the right keywords or select from dozens of confusing filters. Just describe the part you need, like you would to a teammate.
Prompt: "Find an off board molex connector with 2x6 pin configuration at 2.4mm pitch with current ratings of 500mA per pin in the @library."
Copilot interprets the request, runs an intelligent search, and returns a clean table with real components, complete with specs, pricing, availability, and embedded datasheets.
Block diagrams are often your first step in scoping a design. But turning those blocks into real parts usually requires a second, manual pass.
Copilot eliminates that step. If you’ve created a block diagram in Flux, you can just ask:
Prompt: "Generate a BOM from this block diagram. Use parts available in the @library"
Copilot reads the intent behind each block and recommends components that fit, and are available in the library.
When you're new, it's hard to even know what to ask for. That's why Copilot uses the context of your design, voltage rails, interfaces, or constraints you've already defined, to guide its recommendations.
This is also where Copilot’s Knowledge Base really shines. If you’ve saved your preferred components, naming conventions, or layout guidelines, Copilot can use that information automatically, so its suggestions are already aligned with how you like to design.
Prompt: "Find a STM32 IC that has over 32 GPIOs, peripherals for 2x full SDIO, 2xI2S busses, and 3 QSPI busses from the @library"
Instead of a long list of generic op-amps, you’ll get options that fit the electrical and mechanical requirements of your board, with spec highlights that make it easier to choose.
If you're an experienced designer, you already know what you're looking for. But the search process still gets in your way, especially when you’re comparing subtle trade-offs, juggling PDFs, or jumping between tools.
Copilot now lets you move from part search to placement in one continuous thread.
Looking for second sources or similar components? Copilot understands part families and common alternatives.
Prompt: "I want to add an STM32I0 from the @library to this project. Can you recommend one from that family I can use?"
You’ll get a curated set of variants from different vendors, with key spec differences called out and datasheet previews inline. You can quickly assess whether a part meets your requirements, without opening five PDFs.
Context switching kills momentum. You find a part in one tool, then you’re off hunting for its symbol, then toggling over to assign a footprint, then digging through menus just to place it in your schematic. That back-and-forth might not seem like much, but multiply it by dozens of parts, and it adds up fast.
Copilot keeps you in the flow. Once you’ve found the right part, you can take action on it right in the same conversation. Search, validate, and place, all within the same conversation.
Prompt: "I wanto add a TCPP01-M12 from the @library to help protect my circuit electrically from the USB-C connector. Can you help me find it?
You can go from idea to implementation without friction:
Prompt: "Find an MCU for a low-power IoT node."
Prompt: "Place STM32L4R9 in my schematic."
Copilot pulls context-aware results, then places your selection with the right footprint and symbol directly into your schematic. This also works for passives, modules, and more complex components.
Prompt: "Add a resistor divider for a 12V to 3.3V conversion using 1% resistors."
With one thread, you go from requirement → component → placement, all without breaking your flow .
We’ve all been there, clicking through six different datasheets just to confirm one pinout or cross-check a quiescent current value. It’s slow, tedious, and pulls you out of your design flow.
If you're down to two op-amps with nearly identical specs, Copilot can analyze their datasheets and save you 5–10 minutes per part, and help you catch subtle but important differences before committing.
Prompt: "Show me 10 V LDOs under 100 µA quiescent current for battery-powered sensors."
You'll get a table with all the essentials, and you can inspect the PDFs directly, just like you would with tabs and downloads, but without the friction.
What makes this all possible? Behind the scenes, Flux Copilot now uses a combination of two powerful AI strategies: Hybrid Retrieval-Augmented Generation (Hybrid RAG) and an agentic search planning system built specifically for part discovery.
Let’s unpack that.
Hybrid RAG is the foundation, it runs two search engines in parallel:
Copilot fuses both results and re-ranks them based on relevance, so you're more likely to get answers that are both accurate and contextually useful. You don’t need to write the perfect query. Just describe what you need, and Copilot translates it into both a keyword and a semantic search behind the scenes.
But that’s just the starting point.
Copilot doesn’t just run one query and hope for the best. It creates a search plan, executes it, evaluates the results, and adapts, iterating until it finds components that truly match your design intent.
It knows, for example:
This matters because part search isn’t just about finding “a component that works.” It’s about finding parts that fit your schematic, your layout, your budget, and your workflow. And Copilot does that autonomously, in the background, while keeping you in control.
Think of it like designing for both performance and manufacturability. Copilot doesn’t stop at meeting the spec, it helps optimize for the full stack of constraints you care about as a hardware designer.
The result is a part search engine that behaves less like a query box, and more like a teammate who’s thinking alongside you.
The new part search is live now:
As hardware designers ourselves, we built this to remove friction and help you move faster, whether you're validating a quick prototype or heading into production.
Try it out, and if you have thoughts, questions, or edge cases you want to test, we’d love to hear about them in the Flux Slack Community.
This post will give you a deeper understanding of how Flux Copilot works, how large language models (LLMs) and agentic systems operate under the hood, and why grounding them in engineering context matters.
This post will give you a deeper understanding of how Copilot works, how large language models (LLMs) and agentic systems operate under the hood, and why grounding them in engineering context matters. You'll walk away with concrete strategies to get better results — and a clearer sense of how your feedback can shape the future of AI-assisted design.
If you've ever used an AI tool and felt disappointed, you're not alone. Engineers expect precision, and sometimes get something unpredictable. However, that doesn’t mean AI is overhyped. Rather, it means AI is evolving, and we need to learn how to work with it.
AI — especially large language models — is already an incredibly powerful tool. It can synthesize knowledge from thousands of documents, surface insights instantly, and assist in real-time decision-making. But like any tool, it needs to be used correctly. Understanding how it works helps you unlock its full potential.
That’s why we’re writing this. The more you understand how Flux Copilot works under the hood, the more empowered you’ll be to use it effectively, and help shape what it becomes.
At the core of Copilot is a large language model (LLM) — a deep neural network trained on massive datasets to predict the next token in a sequence. In practice, this means it can understand natural language prompts, reason across technical contexts, and generate structured responses.
LLMs aren't "search engines" or "knowledge bases." They don’t retrieve information, they generate it, based on patterns learned during training. This is both their power and their risk: they can generalize across domains and produce fluent output, but they can also produce confident-sounding nonsense — what we call hallucinations.
That’s why Copilot isn’t just a raw LLM. It’s an LLM grounded in structured, trustworthy data:
By combining generative reasoning with factual, contextual inputs, we reduce hallucinations and increase the reliability of Copilot’s suggestions. But it's not bulletproof. It can still generate plausible-sounding errors if the grounding data is missing, incomplete, or misinterpreted.
Copilot isn't operating in a vacuum. It's more than just an LLM generating text — it's an AI agent with access to real tools, structured data, and your active design context. Because it understands your schematic — the parts you’ve used, their interconnections, net names, designators, and annotations — it can reason about your design.
Under the hood, Copilot is connected to a series of tightly integrated tools, each exposing a specific capability:
Together, these tools give Copilot the ability to behave more like a true assistant with systems-level access — not just a text generator.
This kind of functionality bridges the gap between assistant and collaborator. It’s what makes Copilot feel less like a chatbot and more like a teammate. A junior engineer who doesn’t just explain what to do — but starts doing it.
And because Copilot isn’t just responding in a chat bubble — it's connected to your active design — it can take actions: edit the schematic, add components, modify net connections, and flag inconsistencies.
LLMs are generative. They don’t pull facts from a database — they generate answers word by word, based on statistical likelihood. This means they can hallucinate: confidently stating something that sounds plausible but is completely false.
In hardware design, hallucinations can show up as incorrect pin mappings, wrong default values, or oversimplified assumptions. This can lead to real mistakes if the user isn’t validating what Copilot outputs.
While Copilot can take actions inside your project — like editing schematics or inserting parts — some actions may succeed, others may only partially complete, and some prompts might be misunderstood altogether. This is especially true in more complex scenarios, where multiple steps or system-level understanding is needed. The goal is a seamless experience where intent leads to correct execution, but today, users should still expect to guide and verify every step.
Grounding Copilot in real data — through datasheets, project context, and part metadata — helps reduce these risks. But it doesn’t eliminate them. The model might overlook a constraint, misread a spec, or provide a solution that looks reasonable but doesn’t work in practice.
It’s essential to treat Copilot as you would a junior team member: capable, fast, but not infallible. Always review its suggestions. Provide feedback. Ask clarifying follow-ups. That interaction is what turns AI into a truly useful design partner.
We’re also actively working on helping Copilot surface uncertainty — so it can tell you when it’s guessing, and explain what it's basing its answers on (or what information it lacks).
Using Copilot effectively is less about being technical and more about being clear. It’s like working with a new hire who’s smart but unfamiliar with your preferences. The more context you give it, the better it performs.
If you’re looking for a regulator, don’t just say “add an LDO.” Try something like:
“Suggest a 3.3V LDO for an ESP32 with <100uA quiescent current and SOT-23 footprint.”
That level of detail dramatically increases the relevance of the result.
And because Copilot sees your schematic, you can ask things like:
“Which nets are missing decoupling capacitors?”
“Wire up a power tree for these ICs.”
“Add pull-ups to all I²C lines.”
These are tasks that might take you 10–15 minutes. Copilot can do them in seconds — not because it knows better than you, but because it has access to the same information and applies it faster.
You can also refine prompts through iteration. If a response misses the mark, say:
“That’s too high power — optimize for <10mA draw,”
or
“I’d prefer a Texas Instruments part here.”
Copilot remembers the context of your project and previous replies. Treat it like an interactive design partner, not a search engine.
Getting better results with Copilot’s action-taking features — especially for part insertion and wiring — requires a bit of strategy. When asking Copilot to add parts, keep your request scoped to a small, related group of components. For example, instead of saying
“add a power supply,”
try
“Add an 500mA 3.3V linear regulator with a ceramic input capacitor and output capacitors,”
This helps Copilot reason about the function and relationships between components.
Similarly, when wiring things up, ask Copilot to connect two or three components at a time — like wiring up a sensor to a microcontroller with the necessary pull-ups — rather than asking it to connect an entire subsystem in one go. This makes the task more manageable, and improves the accuracy and completeness of the result.
And when it comes to reviewing your work, Copilot can already identify common mistakes, missing components, or inconsistent naming. As we continue building, that design review capability will become even more comprehensive — combining simulation, datasheet validation, and layout context.
Everything we’ve shown so far — contextual understanding, structured reasoning, agentic actions — is just the beginning. The real goal is to make hardware design more fluid, iterative, and collaborative.
We’re building toward a future where describing what you want is enough to begin the design process. Where Flux Copilot understands your intent, accounts for constraints, and takes meaningful steps forward — not just by suggesting, but by executing.
Imagine typing:
“Design a BLE-enabled temperature sensor with 6-month battery life. Optimize for low power.”
And Copilot delivers:
This isn’t sci-fi. It’s the direction we’re actively building toward — and your feedback plays a big role in making it real.
Copilot improves fastest when it’s used by real engineers solving real problems. Here’s how you can help:
Give feedback — What did Copilot do well? Where did it fall short? Be specific.
Train it — Add your naming rules, preferred suppliers, or circuit patterns to Copilot Knowledge.
Push it — Ask for things you wish it could do. Even if it can’t yet, your input helps shape what we build next.
You're not just using a tool. You’re helping define what engineering looks like when AI becomes part of the workflow.
Let’s build it together.
Design high-performance buck converters with proven PCB layout best practices. Cut noise, save space, and optimize your power supply design with this guide.
At its heart, a buck converter is nothing more than three core elements working together to regulate a higher voltage to a lower voltage—and understanding these will make everything else click.
Here’s the simple math for a 12 V→5 V converter:
That 42 % duty cycle tells the MOSFET exactly how long to stay on each cycle so the LC filter averages out to 5 V.
Behind the scenes, a control IC monitors the output, compares it to an internal reference, and tweaks that duty cycle in real time to handle changing loads or input swings. But regardless of controller complexity, the switch + inductor + filter always remain the converter’s heart and soul.
Pick the wrong inductor, and you may face problems like overheating, excessive output ripple, or even core saturation that starves your load under sudden demand. To help you choose wisely, here’s what every beginner EE should know about inductor characteristics:
Pro tip: Choosing an inductor with a bit of extra saturation current rating and modestly lower DCR gives you valuable headroom during prototyping—preventing unexpected heat and ripple issues as your load conditions change.
A combination of MLCCs and a bulk cap covers ripple from kHz to MHz—get this wrong, and you’ll hear audible squeals or see output spikes.
Deep dive: MLCCs lose capacitance under DC bias and heat. And yes, they can sing! Ensure parallel MLCCs are carefully secured mechanically to mute piezo effects. Placing smaller-value capacitors first help to attenuate the high frequency singing in the larger smoothing caps.
Having chosen your parts, layout is your next battleground. The difference between a noisy, inefficient converter and a clean, reliable one often comes down to copper placement. Follow these steps to keep that switching loop tight and your ground plane unbroken.
Remember: “Keep the switching loop tiny and the ground plane continuous.”
Minimize the Switch Loop
Separate Control Signals
From full DIY assemblies to one-click, ready-to-use modules, these different topologies trade off flexibility, board space, and time-to-market. Pick the one that fits your project rhythm.
Each template already includes polygon pours for power and ground, and via-stitching. Once cloned, customize only what matters.
Ground planes are a default in any Flux project, which reflows around all parts and pads to help with noise isolation. Polygons are now in Flux helping you leverage wide current paths for your output voltage to flow through. Adjust thermal reliefs, keep-outs, and copper weights without redrawing anything.
🤖 Copilot: Your AI EE Mentor:
Stuck on compensation loops or gate-resistor values? Ask Copilot right inside the editor. It explains theory, suggests values, and even pulls tables from datasheet PDFs.
🛣️ Auto-Layout for Non-Critical Nets:
Zone off low-speed signals—UART, I²C, sensors—and let Auto-Layout handle them. That frees you to hand-route the critical buck loops that define performance.
“Copilot help me determine the best orientation of U1 to minimize the switching current loop.”
Think of this as your design checklist: tape it to your monitor, keep it next to your keyboard, or fold it in your notebook. Pull it up whenever you need a formula, a layout reminder, or a topology refresher.
With Flux’s polygons, AI Copilot, and Auto-Layout, you’ll spend less time wrestling nets and more time optimizing your power stage—so you can ship faster and with confidence.
👉 Get started now » Open Flux and Clone a Buck Converter
Now, Flux Copilot can learn how you work—your design principles, part selection preferences, schematic style guidelines, and testing workflows—and remember them automatically.
That’s why we built Copilot Knowledge: a way to offload your internal mental graph into something persistent, reliable, and AI-accessible. Now, Flux Copilot can learn how you work—your design principles, part selection preferences, schematic, and testing workflows—and remember them automatically.
It’s like onboarding a new teammate who can understand and distill your process, catches inconsistencies, and applies the right context when you both need it. But this isn’t just memory—it’s leverage. Copilot uses its knowledge to improve its suggestions and take smarter actions helping you move faster with fewer mistakes.
And the best part? You don’t have to change the way you work. Just talk to Copilot as you normally would. When it detects a relevant insight, it’ll ask if you want to save it. Approve what matters, and your personal or project-level Knowledge base builds naturally over time. Let’s dive in!
Knowledge is persistent memory for your Copilot. It stores reusable instructions, tribal knowledge, and workflow guidance that help Copilot work more like you do.
You can teach Copilot anything that improves its judgment across tasks:
This means Copilot can tailor its help based on your intent and context—not just the immediate task at hand.
As you chat with Copilot, it now looks for teachable moments. If you say something like:
“Always use TI parts for voltage boosters” or
“Start every layout with DRC checks”
Copilot will offer to turn that insight into a reusable Knowledge entry.
You can accept, reject, or refine it. Once accepted, it becomes part of Copilot’s working memory. And the next time you’re designing a similar circuit, it’ll know to apply that guidance without being asked.
You can also manually add entries from your profile or project settings. Every Knowledge entry you create makes Copilot smarter and more aligned with how you think.
Every time you save a piece of Knowledge, you can decide where it should apply: just to this project, or to everything you work on going forward.
If you choose project-level, Copilot will only use that Knowledge within the specific project it was saved in. This is ideal for capturing things like client-specific standards, board-specific constraints, or one-off decisions that aren’t relevant elsewhere.
If you choose user-level, Copilot will use that Knowledge across all your future designs. This is where you’ll save broader design habits—like how you label nets, the parts you tend to default to, or your general approach to testing.
Scoping Knowledge like this keeps Copilot flexible. It lets you define reusable standards when it makes sense and isolate exceptions when needed—just like you would when explaining something to a junior engineer stepping into a new design.
Getting the most out of Copilot Knowledge is a lot like onboarding a new hire. The more context you give early on, the more independently—and accurately—they’ll be able to contribute.
When Copilot suggests saving a Knowledge entry, it's your opportunity to share something you’d normally explain to a colleague joining the project for the first time. That might be a naming convention you always use, a preferred component vendor, a filter that’s worked well in the past, or a key review step you never skip. These kinds of insights are rarely documented—but they’re essential to maintaining quality and consistency in real designs.
You don’t need to front-load everything. Knowledge builds naturally over time. But with just a little intentional input, Copilot becomes a design partner who doesn’t just follow your lead—it understands how you lead, and why.
Copilot Knowledge is available now, and there’s nothing new to learn to start using it. Just keep working the way you already do. As you chat with Copilot, it will surface patterns and insights you’ve taught it—then offer to save them as reusable Knowledge.
Start with something simple. A naming convention you always use. A go-to part family. A review checklist. Save that, and keep going. Over time, your Knowledge base grows with you—project by project, decision by decision—until Copilot starts feeling less like a tool and more like a teammate who’s been working with you for years.
This is how design becomes more scalable, more consistent, and more collaborative—without slowing you down.
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This guide is here to help. Based on the most common questions we hear from our users, it walks through practical solutions to unblock your designs and give you more confidence as you build.
Flux is built to help you move fast—from idea to fully routed board—with powerful automation, AI-assisted design, and intuitive tools that make professional workflows accessible to everyone. But even the best tools come with a learning curve, and occasionally you might run into something unexpected.
This guide is here to help. Based on the most common questions we hear from our users, it walks through practical solutions to unblock your designs and give you more confidence as you build.
Whether you’re new to PCB design or just new to Flux, these tips are designed to save you time and help you get the most out of the platform.
“Why am I seeing DRCs for overlapping copper?”
Overlapping copper errors typically occur when copper from two different nets occupies the same area on a PCB layer. This can lead to short circuits, unexpected connections, and compromised board performance. Flux flags these cases as design rule violations to protect the electrical integrity of your design.
Tip💡: Enable all layers in your visibility settings. Overlaps sometimes occur between nets on different layers and can be easy to miss.
“Why is Flux saying I have conflicting fills?”
Flux automatically adds GND fills to each layer, but if more than one net is assigned a fill on the same layer, it creates a conflict. The system prevents this to ensure clean and predictable copper behavior.
Only one net should apply fills per layer—typically GND, unless you're working on advanced designs requiring power planes or split fills.
“What is floating copper, and why is it an error?”
Floating copper refers to any copper (usually a fill or trace) that is no longer electrically connected to its assigned net. This often happens when components are moved or deleted, leaving behind orphaned copper.
Keeping copper grounded and connected ensures electrical correctness and helps avoid manufacturing issues down the line.
“My board has no visible GND fills—what’s wrong?”
By default, Flux adds ground fills to all PCB layers for the GND net. If you’re not seeing them, it’s usually a configuration or visibility issue rather than a bug.
Fills play a crucial role in EMI reduction, return path continuity, and thermal performance, so it's important to verify they're in place.
“I created a part, but I can’t find it in my library—where is it?”
When you create a custom part in Flux, it lives in a separate project until you publish it. Publishing is what makes it available in your global or team library.
🔒 By default, newly created parts are private.
If you want others to use it, click “Share” and set visibility permissions. Just remember to re-publish after updating sharing settings.
“I imported my Altium file, but nothing shows up.”
This usually comes down to format. Flux only supports ASCII format when importing from Altium Designer. If you export in binary format, the import will silently fail or appear blank.
To verify: open the file in a text editor. If it’s human-readable, it’s ASCII. If it’s gibberish, it’s binary.
Large schematics? Try breaking them into modules for smoother imports.
“Why is Auto-Layout stuck on ‘Optimizing’?”
Flux’s Auto-Layout feature can take time—especially on complex boards. The “Working” state may appear stuck if DRCs are unresolved, or if the board has high routing complexity.
If needed, hit Stop to investigate and restart. Just be aware that stopping clears progress if changes haven’t been applied.
“I imported a KiCAD part—why is it incomplete?”
Flux supports KiCAD library imports, but some metadata—like footprints or 3D models—need to be linked manually.
Once set, the part will behave like any other in your library.
“Why is Copilot making strange connections?”
Flux Copilot is optimized for specific, context-aware actions. It’s not intended to auto-wire an entire schematic in one go, and complex instructions often reduce its accuracy.
With more focused prompts, Copilot becomes a powerful assistant rather than a source of confusion.
“Where can I go when I need support fast?”
We want you to feel confident using Flux, even when things aren’t going smoothly. Here's how to get help:
Building with Flux means working with one of the most forward-moving platforms in EDA—but we also know that speed comes with bumps along the way. This guide is here to help you smooth them out and keep shipping.
Most importantly, you’re not alone. Whether it’s a UI quirk, a Copilot misfire, or just needing a second pair of eyes, we’re here to help—through docs, videos, chat, or Slack.
And if something isn’t working the way you expect, let us know. The fastest way we improve Flux is with your feedback.
