Altium Designer dominates as the premium printed circuit board layout solution, fusing powerful features with intuitive usability. This guide will walk you through a full PCB design project in Altium to demonstrate essential capabilities and workflows.
Follow along as we:
- Create schematics and circuitry
- Develop board outlines and mounting
- Set design rules and plane layers
- Route signals across multiple sheets
- Validate designs with ERC and DRC
- Generate manufacturing outputs
By the end, you’ll grasp the comprehensive tools at your fingertips to transform concepts into professional multilayer PCBs. Let’s dive in!
Creating the Schematic
We start off by opening Altium and building schematics to define our circuitry components and connectivity.
Configuring Design Settings
We begin by tweaking some project-wide settings through the Preferences menu for this simple single-voltage board:
1. Set voltage colors – Single 3.3V supply 2. Disable room borders 3. Enable autojunctions 4. Set default line width - 10mil
This streamlines the schematic capture process with less clicks.
Placing Components
Next, we drag symbols onto the blank schematic sheet to map our conceptual circuit:
- Microcontroller unit (MCU)
- Crystal oscillator
- Decoupling capacitors
- Power supply circuitry
- Indicator LEDs
- Peripheral connectors
It quickly starts to take shape.
Wiring Connectivity
We complete the schematic by popping open the Connectivity mode and tying pins together to form logical nets:
The rat’s nest mesh visualizes desired connections to route cleanly.
Annotating the Schematic
Final callouts include:
Reference Designators - U1, R5, C2 etc.
Pin Numbers – Showing locations to connect
Net Labels – Symbolic groups like VCC, DATA, ENABLE
Component Comments – Part numbers, values, ratings
This produces our finished roadmap to implement the concept electrically!
Transition to PCB Layout
With schematic capture completed, we migrate the connective data to the physical PCB editor to carefully lay out components and route copper traces between them.
Import into Board Planner
Inside the PCB editor, we import the netlist connectivity from our schematic using the Design » Import Changes command. This transfers components, pins, and nets.
We have officially entered the layout realm!
Defining Layer Stack
The next step configures the layer stackup through Design » Layer Stack Manager by inserting conductive copper and dielectric layers to route between vertically.
For this demo, we’ll assume a 4-layer board with:
- Top & Bottom Signal Layers
- VCC Plane
- Ground Plane
This supports routing signals upstairs and downstairs.
Floorplanning Footprint Placement
With layers prepped, we transition into Board Planning mode to arrange components. Dragging part symbols from libraries, we visually block in sections:
Grouped functional sections emerge - power supply, indicators, control, peripherals.
We orient connectors and set dimensions by drafting board profile lines. The basic platform takes shape!
Developing the PCB Layout
Now the fun truly begins transforming the floorplan into an electrified PCB by routing traces and integrating plane layers.
Routing Signals Between Components
We enter Interactive Routing mode connecting nets between component pads across the Top and Bottom layers following schematic logic flows:
The rats nest untangles as traces relay signals port-to-port!
Applying Power Planes
Next we divide the VCC and ground nets onto plane layers for low impedance power distribution. The Plane tool fills unused area:
We toggle layers to visually confirm complete flooding between pads/vias.
Finalizing the Board Shape
With signals routed and planes applied, we flip back into Board Planning mode to finish the board profile.
Using a dimension tool, rectangular lines trace the desired size. Circles mark drill holes for mounting or connectors.
This concludes core layout drafting before design analysis and manufacturing prep.
Validating the PCB Design
To formally check for issues before sending the design out, we run Electrical Rules Check (ERC) and Design Rules Check (DRC) tools. This verifies connectivity and physical specifications.
Executing the Electrical Rules Check
The ERC scans schematic document files and pin-to-pin connections between schematic and board layout detecting unmatched signals between sheets. Any errors appear:
We remediate missed connects to pass ERC cleanly.
Running Design Rules Check
We also probe the physical PCB document checking parameters like:
- Trace width/spacing
- Mask expansion
- Via sizes
- Clearances
DRC flags any insufficient margins against the defined constraints:
Errors here might require trace fattening, component rotations, or layer tweaks to dial in proper margins.
With ERC and DRC passing without warnings, we clear release the design for production!
Manufacturing Generation & Conclusion
As a final production prep step, we produce comprehensive fabrication and assembly files including:
- Gerbers - Layer images for board fabrication
- NC Drill - Hole locations for machining
- BOM - Part list for pick-and-place assembly
- Positional Info - Centroid data to orient components
After zipping outputs, we forward to the board house for prototyping and testing!
That concludes the journey through a complete start-to-finish PCB project within Altium covering key features and steps along the way.
The beauty of Altium lies in its unified design environment - easing the transition from schematic ideation down through physical PCB implementation while preventing mismatches.
You should now feel comfortable navigating the core workflow to mobilize a basic PCB design. But there are many additional tools and nuanced functions to master across the platform - so keep pushing your Altium skills upward through continued education and experimentation guided by this tutorial foundation!
FAQ
Here are some common questions about designing PCBs in Altium:
What are the software requirements to run Altium?
Altium supports Windows 7 or 10. 16GB RAM is recommended for complex designs along with graphics card carrying 1GB+ GPU memory and OpenGL 3.1 support.
Does Altium connect with version control or database tools?
Yes, Altium includes native integration with SVN and Git for version control. It can link to external SQL and MongoDB databases to store metadata.
What file formats can Altium import/export?
Altium imports: SPECCTRA, Cadence Allegro and OrCAD, Eagle, PADS, Xpedition, and more. It exports industry standard Gerbers, STEP models, PDFs, Excel BOMs, etc.
Are there limitations on the number of layers?
No practical limits. Users have designed boards with 100+ layers given requisite fabrication capabilities. Only computer memory sets ceilings.
Can error reports be customized?
Yes, extensive flexibility exists to configure proprietary checks and constraints for ERC/DRC testing during validation. Custom queries can also probe designs.
That wraps up the Q&A. Let me know if you have any other questions!
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