matlab-write-pcb-layout

Writing PCB Layouts to Manufacturing Files

When to Use

Exporting a pcbComponent or pcbStack design to Gerber manufacturing files
Selecting and configuring RF connectors (SMA, SMB, MMCX, etc.) for PCB export
Formatting output for specific fabrication services (OSH Park, Seeed, Advanced Circuits)
Attaching RFConnector objects to catalog components for shielded analysis
Generating a complete manufacturing package from a MATLAB RF design

When NOT to Use

Importing Gerber files into MATLAB — use matlab-read-pcb-layout
Building the PCB design itself — use matlab-assemble-pcb-layout or the designing skills
Running EM analysis — use matlab-analyze-em

Typical Workflow

Before: A design skill or matlab-assemble-pcb-layout — create the pcbComponent; matlab-analyze-em — validate performance; matlab-optimize-pcb-design — tune if needed
This skill: Export to Gerber with connectors and fab formatting

Quick Reference

Task	Code
Export Gerber files	`[A,g] = gerberWrite(pcb, W, {C1,C2})`
SMA connector	`C = PCBConnectors.SMA_Cinch`
Edge-launch SMA	`C = PCBConnectors.SMAEdge_Samtec`
PCB service writer	`W = PCBServices.OSHParkWriter`
Customize writer	`W.Filename = 'name'; W.CoordUnits = 'mm'`
RF connector object	`rc = RFConnector`
Design connector for PCB	`rc = design(RFConnector, pcb)`

gerberWrite — Export to Manufacturing

The gerberWrite function generates manufacturing files from a pcbComponent.

Basic Export

p = pcbComponent;   % Your designed component
W = PCBServices.OSHParkWriter;
W.Filename = 'my_design';          % Controls output zip/folder name (default: 'untitled')
C1 = PCBConnectors.SMA_Cinch;
C2 = PCBConnectors.SMA_Cinch;

[A, outputPath] = gerberWrite(p, W, {C1, C2});

Output

gerberWrite produces a folder of Gerber and drill files:

Top/bottom copper layers
Solder mask layers
Silkscreen layers
Drill files
Board outline

The A output is a PCBWriter object with export metadata. outputPath is the path to the generated files.

PCBWriter Object

The PCBWriter object controls export settings.

Properties

Property	Description
`Design`	Struct containing the PCB design data
`Writer`	The PCB service writer (output format)
`Connector`	Cell array of connector objects
`UseDefaultConnector`	Use default connector if none specified
`ComponentBoundaryLineWidth`	Outline line width
`PCBMargin`	Extra board margin around component (m)
`Soldermask`	`'both'`, `'top'`, `'bottom'`, or `'none'`
`Solderpaste`	Logical — generate solderpaste layer
`Font`	Font for text on silkscreen

PCBConnectors — Connector Catalog

Attach standard RF connectors to your exported board.

Available Connectors (25 Built-in Types)

Category	Connectors
SMA 5-Pad	`SMA`, `SMA_Cinch`, `SMA_Multicomp`
SMA Edge-Launch	`SMAEdge`, `SMAEdge_Cinch`, `SMAEdge_Samtec`, `SMAEdge_Amphenol`, `SMAEdge_Linx`
SMB/SMC	`SMB_Johnson`, `SMB_Pasternack`, `SMC_Pasternack`, `SMCEdge_Pasternack`
MMCX	`MMCX_Cinch`, `MMCX_Samtec`
IPX/U.FL	`IPX_Jack_Lighthorse`, `IPX_Plug_Lighthorse`, `UFL_Hirose`
Coaxial Cable	`Coax_RG11`, `Coax_RG58`, `Coax_RG59`, `Coax_RG174`
Semi-Rigid	`Semi_020`, `Semi_034`, `Semi_047`, `Semi_118`

Access via PCBConnectors.<type>. All connectors have common properties: Type, Mfg, Part, Annotation, Impedance (default: 50 ohm), Datasheet, Purchase.

5-pad properties: TotalSize, GroundPadSize, SignalPadDiameter, PinHoleDiameter, IsolationRing, VerticalGroundStrips

Edge-launch properties: GroundPadSize, GroundSeparation, GroundPadIsolation, SignalPadSize, SignalGap, SignalLineWidth, EdgeLocation ('north'|'south'|'east'|'west'), ExtendBoardProfile, FillGroundSide

Coax properties: PinDiameter, DielectricDiameter, ShieldDiameter, AddThermals, ThermalsDiameter, ThermalsBridgeWidth

Connectors are placed at feed locations during Gerber export. They define pad footprints and drill patterns.

PCBServices — Fabrication Service Writers

Writers configure output for specific fabrication services.

Available Services (5 Built-in Writers)

Service	Description
`PCBServices.GerbLookWriter`	GerbLook online viewer
`PCBServices.ZofZWriter`	ZofZ 3-D Gerber viewer
`PCBServices.AdvancedCircuitsWriter`	Advanced Circuits manufacturing
`PCBServices.SeeedWriter`	Seeed Studio manufacturing
`PCBServices.OSHParkWriter`	OSH Park manufacturing

Each writer formats Gerber files according to the fab house's naming and layer conventions.

Key PCBServices properties: Filename, CoordUnits ('in'/'mm'), CoordPrecision, CreateArchiveFile, DefaultViaDiameter, UseExcellon, BoardProfileFile, SameExtensionForGerberFiles, PostWriteFcn, Files

% Customize a service writer
w = PCBServices.AdvancedCircuitsWriter;
w.Filename = 'my_antenna';
w.CoordUnits = 'mm';
w.CoordPrecision = [3 4];

RF Connectors

RFConnector models coaxial connectors (SMA, SMB, etc.) that attach to PCB structures.

rc = RFConnector;
rc.InnerRadius  = 5e-4;      % Center pin radius
rc.OuterRadius  = 1.5e-3;    % Outer conductor radius
rc.PinLength    = 3e-3;      % Pin insertion depth
rc.PinFootprint = 'Taper';   % 'Taper' or 'Circular'
rc.EpsilonR     = 1.7341;    % Dielectric fill permittivity
rc.Impedance    = 50;        % Characteristic impedance

Attaching to a Catalog Object

Attaching a Connector to a catalog object (e.g., microstripLine) requires IsShielded = true:

m = microstripLine;
m.IsShielded = true;          % Required before setting Connector
m.Connector = RFConnector;
show(m);

Design for a pcbComponent

design() auto-tunes connector dimensions to match a PCB object. This requires an FEM-based pcbComponent — catalog objects like microstripLine do not support FEM:

pcb = pcbComponent;           % Must be pcbComponent with SolverType='FEM'
pcb.SolverType = 'FEM';
rc = design(RFConnector, pcb);

Complete Design-to-Manufacturing Workflow

%% Design a filter
f = design(filterCoupledLine, 3e9);

%% Analyze
freq = linspace(1e9, 5e9, 101);
sp = sparameters(f, freq, 'SweepOption', 'interp');
rfplot(sp);

%% Export for manufacturing (convert to pcbComponent first)
pcb = pcbComponent(f);
W = PCBServices.OSHParkWriter;
C1 = PCBConnectors.SMA_Cinch;
C2 = PCBConnectors.SMA_Cinch;
[A, gPath] = gerberWrite(pcb, W, {C1, C2});

Pitfalls

Connector compatibility: Not all connectors work with all board thicknesses. SMA edge-launch connectors assume standard substrate heights. Check connector footprint dimensions match your board.
Gerber aperture limitations: Complex curved geometries may be approximated with polygons in Gerber format. Very fine features may lose resolution during export — check minimum feature size for your target fab service.
Multiple connectors need cell array: When passing multiple connectors to gerberWrite, wrap them in a cell array: gerberWrite(pcb, W, {C1, C2}). An object array [C1, C2] will error.
gerberWrite requires pcbComponent or pcbStack: gerberWrite does not work on catalog objects (e.g., microstripLine, filterHairpin). Convert to pcbComponent first if needed.
Connector requires IsShielded on catalog objects. Setting obj.Connector = RFConnector on a catalog object (microstripLine, etc.) will error with "SolverType property must be set to 'FEM'" unless obj.IsShielded = true is set first. Catalog objects do not support FEM directly — use IsShielded = true for MoM shielded mode. design(RFConnector, obj) only works with pcbComponent objects that have SolverType='FEM'.
IsShielded + finite conductivity conflict. Setting IsShielded = true activates an internal FEM-like solver path. If you also set Conductor = metal("Copper") (finite conductivity), you will get "FEM solver does not support finite conductivity. Set conductivity of conductor to Inf." Leave Conductor at the default (PEC) when using IsShielded = true or Connector.
gerberWrite on pcbcascade results. pcbcascade returns a pcbComponent. This can be passed directly to gerberWrite. However, verify the port count and connector count match — pcbcascade merges ports and removes connected ports, so the surviving port count may differ from the input components.
IsShielded switches solver to FEM — affects sweep options. Setting IsShielded = true changes the internal solver to FEM. The 'SweepOption', 'interp' interpolated sweep is designed for MoM and may not be available or behave differently with FEM. Run S-parameter analysis before adding IsShielded for export, or use a discrete frequency sweep with FEM.

Related Skills

matlab-read-pcb-layout — Import layouts from Gerber, ODB++, and Allegro
matlab-assemble-pcb-layout — Building custom PCB structures from shapes
matlab-analyze-em — Running EM analysis before export