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PCB capabilities

Find the specifications that matter to your next board.

Explore materials, dimensions, design rules and assembly requirements in one place.

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Check the limits for your material, layer count and process together. For special requirements, contact our team before ordering. Select a diagram to enlarge it.

Rigid PCB capabilities

PCB Specifications
FeaturesCapabilityDescriptionDiagram
Layer count1-32 LayersThe number of copper layers in the PCB
Controlled Impedance4/6/8/10/12/14/16/18/20/.../32 layersImpedance-controlled PCB design supportAsk about impedance and stack-up
Impedance Tolerance±10%
MaterialFR-4Grade A laminates from suppliers including Nan Ya, KB, Shengyi and etc.fr4 pcb material stackup
MaterialAluminum-Core1-layer Aluminum-core PCBsfr4 pcb material stackup
MaterialCopper-Core1-layer copper-core PCBs with direct heatsink contacts to core (≥ 1 × 1 mm)fr4 pcb material stackup
MaterialRF PCB1 oz copper, 2-layer RF PCBs with Rogers and PTFE coresfr4 pcb material stackup
FR-4 Dielectric Constants4.5 (2-Layer PCB)

7628 Prepreg 4.4

3313 Perpreg 4.1

2116 Perpreg 4.16

Maximum Dimensions

FR4(1-layer): 606 × 510 mm

FR4(2-layer): 670 × 600 mm

FR4(4-layer): 663 × 593 mm

FR4(6-layer and above): 656 × 586 mm

Rogers / PTFE Teflon PCB: 590 × 438 mm

Aluminum PCB: 602 × 506 mm

Copper PCB: 480 × 286 mm

These limits apply to PCBs with thickness ≥ 0.8 mm. The thinner FR4 PCBs are 599 × 497 mm maximum.

2-layer FR4 PCBs can reach a maximum size of 1020 × 600 mm.

4-layer FR4 PCBs can reach a maximum size of 1016 × 596 mm.

square and round pcb dimensions x y
Minimum Dimensions

FR4/Rogers/PTFE: 3 × 3 mm

Castellated / Plated Edges: 10 × 10 mm

Aluminum/Copper PCB: 5 × 5 mm

These limits apply to PCBs with thickness ≥ 0.6 mm. Manual review required for thinner PCBs. Panelization is recommended for small-sized boards.
Dimension Tolerance±0.1mm±0.1mm(Precision) and ±0.2mm(Regular) for CNC routing, and ±0.4mm for V-scoring
Thickness0.4 – 4.5 mmThickness for FR4 are: 0.4/0.6/0.8/1.0/1.2/1.6/2.0 mm (2.5 mm and above are for 12+ layer PCBs only)pcb thickness measurement diagram
Thickness Tolerance(Thickness≥1.0mm)± 10%e.g. For the 1.6mm board thickness, the finished board thickness ranges from 1.44mm(T-1.6×10%) to 1.76mm(T+1.6×10%)
Thickness Tolerance(Thickness<1.0mm)± 0.1mme.g. For the 0.8mm board thickness, the finished board thickness ranges from 0.7mm(T-0.1) to 0.9mm(T+0.1).
Finished Outer Layer Copper

2-layer: 1 oz / 2 oz / 2.5 oz / 3.5 oz / 4.5oz

Multi-layer: 1 oz / 2 oz

finished outer layer copper stackup
Finished Inner Layer Copper0.5 oz / 1 oz / 2 ozFinished copper weight of inner layer is 0.5oz by default.finished inner layer copper stackup
SoldermaskGreen, Purple, Red, Yellow, Blue, White, and Black.We use LPI (Liquid Photo Imageable) solder mask. This is the most common type of mask used today. Heat-cured ink soldermask is usually found on low-cost, single-sided PCBs.
Surface FinishHASL (leaded / lead-free), ENIG, OSP (Single-sided FR-4, FPC, and aluminum PCBs are currently not supported for OSP)

Aluminum PCBs: HASL only; FR-4/HDI boards with 6 or more layers, boards with a thickness ≤ 0.4 mm, high-frequency boards, copper-based PCBs, and FPCs do not support HASL.

Drilling
FeaturesCapabilityDescriptionDiagram
Drill Diameter

1-layer: 0.3 – 6.3 mm

2-layer: 0.15 – 6.3 mm

Multilayer: 0.15 – 6.3 mm

Holes with diameter ≥ 6.3 mm are CNC routed from a smaller drilled hole.

Min. drill diameter for 2- or more-layer PCBs is 0.15 mm (more costly!)

Min. drill diameter for aluminum-core PCBs is 0.65 mm

Min. drill diameter for copper-core PCBs is 1.0 mm

drill diameter min max diagram
Hole size Tolerance

Through-holes: +0.13 / -0.08 mm

Press-fit holes:±0.05 mm (Finished hole size: 0.55-2.0mm. Multilayer ENIG boards and circular holes only. Mention the specific holes in PCB Remark)

e.g. for the 0.6mm hole size, the finished hole size between 0.52mm to 0.73mm is acceptable.

To avoid soldermask or tin stuck in the hole, recommended PTH size≥0.5mm.

pcb hole size tolerance diagram
Average Hole Plating Thickness18μm
Hole Position Tolerance±0.05 mm
Blind/Buried ViasNot supportedCurrently we don't support Blind/Buried Vias, only make through holes.blind buried vias cross section
Min. Via hole size/diameter0.15mm / 0.25mm

1-layer (NPTH only): 0.3 mm hole size / 0.5 mm via diameter

2-layer: 0.15mm hole size / 0.25mm via diameter

Multilayer: 0.15 mm hole size / 0.25 mm via diameter

① Via diameter should be 0.1mm(0.15mm preferred) larger than Via hole size.

② Preferred Min. Via hole size: 0.2mm

③ 0.15mm hole size with any size via diameter, and 0.2mm or 0.25mm hole size with via diameter less than 0.45mm, will cost more.

min via hole size diameter diagram
Min. Non-plated holes0.50mmPlease draw NPTHs in the mechanical layer or keep out layer.min non plated holes npth
Min. Plated Slots Width

2-layer: 0.5mm

Multi-layer: 0.35mm

The minimum plated slot width is 0.5mm, which is drawn with a pad. The length of the slot should be at least 2 times of the width.min plated slot width dimension
Min. Non-Plated Slots1.0mmThe minimum Non-Plated Slot Width is 1.0mm, please draw the slot outline in the mechanical layer(GM1 or GKO)min non plated slot width
Slot Hole size Tolerance

Plated: +0.13 / -0.08 mm

Non-plated: ±0.2mm

Plated slot is made by drill tools.

Non-plated slot is made by CNC.

Via Hole-to-Hole Spacing0.2mmvia hole to hole spacing diagram
Pad Hole-to-Hole Spacing0.45mmpad hole to hole spacing diagram
Min. Castellated Holes0.5mm

Castellated holes are metalized half-holes on PCB edges, commonly used on daughter boards to be soldered onto carrier PCBs.

① Hole diameter (Φ): ≥ 0.5 mm

② Hole to board edge (L): ≥ 1 mm

③ Hole to hole (D): ≥ 0.5 mm

④ Min. PCB size:10 × 10 mm

⑤ Min. PCB thickness: 0.6 mm

min castellated holes specification
Plated Edges10 x 10mm

Plated edges are copper-plated and ENIG treated. HASL is not supported.

① Min. PCB size: 10 × 10 mm

② Min. PCB thickness: 0.6 mm

③ At least 3 breaks (more for larger PCBs) in the edge plating are required for support tab connections

pcb plated edges demonstration
Blind Slot

① Blind slot width (W): ≥1.0mm

② Blind slot depth (D): ≥0.2mm

③ Blind slot annular width (A): ≥0.3mm

④ Safety distance (S): ≥0.2mm

⑤ Blind slot remaining thickness (R): ≥0.2mm

⑥ Supports 2-32-layer FR4 boards with a thickness of ≥0.8mm

pcb blind slot stackup diagram
Backdrill

Backdrill uses a secondary drilling process to control the depth of the hole, removing excess copper from the other layers of the via, thereby reducing its interference with the signal.

①Supports 4-32-layer FR4 boards with a thickness of ≥0.8mm

②Through-Hole Diameter(D): 0.2-0.5mm(Epoxy filled after backdrilling)

③Backdrill Diameter(W): typically 0.2mm larger than through-hole diameter

④Backdrill Depth(L): layers with backdrilling, customizable

⑤Dielectric Thickness(T): ≥0.15mm

⑥Safety Distance(S): ≥0.2mm

pcb backdrill cross section diagram
Rectangular Holes / SlotsNot supportedRectangular holes and slots without rounded corners are not supported.supported pcb slot shapes guide
Traces
FeaturesCapabilityDescriptionDiagram
Min. track width and spacing (1 oz)0.10 / 0.10 mm (4 / 4 mil)

1- and 2-layer: 0.10 / 0.10 mm (4 / 4 mil)

Multilayer: 0.09 / 0.09 mm (3.5 / 3.5 mil). 3 mil is acceptable in BGA fan-outs.

min trace width spacing diagram
Min. track width and spacing (2 oz)0.16 / 0.16 mm (6.5 / 6.5 mil)

2-layer: 0.16 / 0.16 mm (6.5 / 6.5 mil)

Multilayer: 0.15 / 0.15 mm (6 / 6 mil)

Min. track width and spacing (2.5 oz)2 layer: 0.2/0.2mm(8mil/8mil)
Min. track width and spacing (3.5 oz)2 layer: 0.25/0.25mm(10mil/10mil)
Min. track width and spacing (4.5 oz)2 layer: 0.3/0.3mm(12mil/12mil)
Track width tolerance±20%e.g. For a 0.1 mm track, the finished track width ranges from 0.08 and 0.12 mm.
PTH annular ring≧0.20mm

2-layer:

1 oz: Recommended 0.25 mm or above; absolute minimum 0.18 mm

2 oz: 0.254 mm or above

Multilayer:

1 oz: Recommended 0.20 mm or above; absolute minimum 0.15 mm

2 oz: 0.254 mm or above

pth pad annular ring diagram
NPTH pad annular ring≧0.45mmRecommended 0.45 mm or more. This is to allow a 0.2 mm ring of copper to be removed around the hole for the sealing film to attach.npth pad annular ring diagram
BGA0.2mm

① 0.2mm-0.25mm BGA pad diameter requires ENIG

② BGA pad to trace clearance ≥ 0.1 mm (min. 0.09 mm for multilayer boards)

③ Vias can be placed within BGA pads using filled and plated-over vias

bga pad and via in pad diagram
Trace coils0.15/0.15mm

Minimum trace width/clearance: 0.15/0.15mm, when traces are covered by solder mask (1oz).

Minimum trace width/clearance: 0.25/0.25mm, when traces are NOT covered by solder mask (1oz). ENIG only(high risk of short circuit with HASL)

pcb trace coils enig solder mask
Hatched grid width and spacing0.25 mmhatched grid pattern width spacing
Same-net track spacing0.25mmsame net track spacing diagram
Inner layer via hole to copper clearance0.2mminternal via to copper clearance
Inner layer PTH pad hole to copper clearance0.3mm
Pad to track clearance0.1mmMin. 0.1 mm (stay well above if possible). Min. 0.09 mm locally for BGA padspad to track clearance diagram
SMD pad to pad clearance (different nets)0.15mm

More details of SMD pad spacing: SMD component spacing design support

Minimum SMD pad: 0.25mm × 0.25mm

smd pad to pad clearance diagram
Via hole to Track0.2mmvia hole to track spacing
PTH to Track0.28mm0.35mm is recommended, minimum 0.28mmpth to track clearance limit
NPTH to Track0.2mmnpth to track clearance limit
Soldermask
FeaturesCapabilityDescriptionDiagram
Soldermask Expansion1:1

LDI equipment upgraded in June 2025. Pad size:soldermask opening can be 1:1(Previous production file will be followed in Reorder).

Keep at least 0.09 mm clearance between soldermask openings and neighboring traces.

soldermask expansion and clearance
Soldermask bridge0.10mm

1oz:

Min. pad spacing: 0.10 mm (green, red, yellow, blue, purple)

Min. pad spacing: 0.13 mm (black, white)

2oz:

Min. pad spacing: 0.20 mm (any color)

min soldermask bridge width diagram
Plugged viasFilled with soldermask

Vias are filled with soldermask for an opaque finish. Ask about via covering options

① Filled vias must not have soldermask openings on either side

② Filled vias should have ≥ 0.35 mm clearance from other soldermask openings (e.g. pads)

③ Filled vias must be no wider than 0.5 mm diameter

vias plugged with soldermask ink
JLCPCB Via-in-Pad Process

Epoxy Filled & Capped

Copper paste Filled&Capped

Vias are filled with epoxy resin or copper paste and then plated over to achieve an opaque and smooth finish. Ask about via covering options

① Vias are filled and plated over. Choose copper paste filling for applications requiring high thermal conductivity.

② This process is the default for 6-layer and above multilayer boards.

③ Compatible with via diameters from 0.15 to 0.55 mm.

jlcpcb via in pad stackup diagram
Solder mask dielectric constant3.8pcb solder mask thickness cross section
Solder mask ink thickness≥ 10μm
Legend
FeaturesCapabilityDescriptionDiagram
Minimum Line Width≥0.15mmCharacters width less than 0.15mm will be unidentifiable.silkscreen minimum line width diagram
Minimum text height40 mil (1.0mm)Characters height less than 40 mil(1.0mm) will be unidentifiable.silkscreen minimum text height diagram
Character width to height ratio1:6The preferred ratio of width to height is 1:6.silkscreen width to height ratio guide
Hollow-carved Character width to height ratio1:6The preferred ratio of width to height is 1:6hollow character width to height ratio
Pad To Silkscreen0.15mmThe Minimum Distance Between Pad and Silkscreen is 0.15mm.pad to silkscreen clearance diagram
Outline
FeaturesCapabilityDescriptionDiagram
Routed0.2mm

① Copper clearance from routed board edges: ≧0.2 mm

② Copper clearance from routed slots: ≧0.2 mm

③ Dimension tolerance for routed board edges: ±0.2 mm (regular precision); ±0.1 mm (high precision)

④ Minimum dimension 50*50mm for high precision, and at least 3 tooling holes with minimum 1.5mm diameter on different corners.

⑤ Minimum slot width for aluminum/copper core PCB: 1.6mm.

pcb via solder mask opening process
V-Cut0.4mm

① Copper clearance from V-cut board edges: ≧0.4 mm

② Dimension tolerance for V-cut board edges: ±0.4 mm. PCB thickness ≥ 0.6 mm

③ Zero panel board spacing by default. Alternatively, V-cut along one direction with no spacing and route along the other direction with 1.6 or 2 mm board spacing.

④ Min. panel dimensions: 70 × 70 mm; max. panel dimensions: 475 × 475 mm

⑤ V-cut groove angle: 25°

⑥Minimum spacing between two v-cuts: 2mm(3mm is recommended)

pcb pad solder mask opening process
Mouse bites Panel0.2mm

① Copper clearance from non-mouse-bite board edges: ≧0.2 mm

② Dimension tolerance for non-mouse-bite board edges: ±0.2 mm (regular precision); ±0.1 mm (high precision)

③ Panel board spacing: 1.6 or 2 mm

④ Serrated edges will remain after depanelization

⑤ Minimum tooling edge width: 3 mm. For SMT assembly at JLCPCB, use 5 mm tooling edges, 2 mm tooling holes, and 1 mm fiducials centered at 3.85 mm from the panel edges.

⑥ Recommended diameter of mouse bite is 0.5mm-0.8mm; Recommended distance between the two mouse-bites is 0.2-0.3mm. The minimum width of breakaway tab is 4mm. For breakaway with mouse-bites, the minimum width is 5mm.

pcb mouse bites panel design specs
Panelization with space2mmThe spacing between boards should be ≥ 2 mm, as narrow spacing results in difficulties for routing and V-cut.pcb panelization with minimum spacing
Panel of Circular PCBs≥20mmx20mm

The single round board size should be≥20mmx20mm when choose panel by JLCPCB.

Panelize with stamp holes and add tooling strips on four board edges

circular pcb panel design requirements

Flex PCB capabilities

Flexible PCB Capabilities
Category Features Capability Description
Layer Count1-layer, 2-layers, 4-layersThe number of copper layers in the FPCRigid-flex PCBs are not yet supported.
FPC Stack-Up1-Layer (25µm dielectric thickness)FPC with copper and coverlay on the same one side only. Inner PI thickness: 25 μmfpc 1 layer 25um stackup
FPC Stack-Up2-Layer (25µm dielectric thickness)FPC with copper on both sides. Inner PI thickness: 25 μmfpc 2 layer 25um stackup
FPC Stack-Up1-Layer (50µm dielectric thickness)Tear-resistant.fpc 1 layer 50um stackup
FPC Stack-Up2-Layer (50µm dielectric thickness)Tear-resistant. Suitable for impedance-controlled boards.fpc 2 layer 50um stackup
FPC Stack-Up1-Layer (Transparent)PET Thickness: 36umtransparent fpc 1 layer pet
FPC Stack-Up2-Layer (Transparent)PET Thickness: 36umtransparent fpc 2 layer pet
FPC Stack-Up4-Layer

Inner/outer layer copper weight: 1/3oz, 0.5oz, and 1oz.

Lamination structures: with coverlay or without coverlay.

For inner layers with 1oz copper weight, coverlay is applied by default to prevent delamination and blistering during lamination.

4 layer fpc cross section
DimensionsMaximum DimensionsRegular: 234 × 490 mmAbsolute limit of 250 × 600 mm allowed with edge rails – confirm with customer support before ordering.
DimensionsMinimum DimensionsNo limit, but FPCs whose dimension is smaller than 20 × 20 mm are best panelisedGet help with Flex PCB panel design
DimensionsFPC Finished Thickness

25µm dielectric thickness FPC:

1-Layer: 0.07 / 0.11 mm

2-Layer: 0.11 / 0.12 / 0.2 mm

50µm dielectric thickness FPC:

1-Layer: 0.12 mm

2-Layer: 0.19 mm

Transparent FPC:

1-Layer: 0.14 mm

2-Layer: 0.24 mm

4-Layer FPC: 0.2 / 0.25 / 0.30 / 0.35 / 0.40 / 0.45 mm

①The thickness of the finished FPC excluding any stiffeners (If the measured area has no copper or coverlay, the finished thickness will be reduced.)

②White coverlay is 10um per side thicker than yellow/black coverlay.

DimensionsOuter Layer Copper Weight

Single-sided: 18 μm (0.5 oz), 35 μm (1 oz)

Double-sided & four-layer: 12 μm (0.33 oz), 18 μm (0.5 oz), 35 μm (1 oz)

The thickness of copper on the FPC
DimensionsType of ProcessDry film process with LDI (laser direct image) exposure technologyLDI provides higher accuracy than traditional LED exposure. The machines also support automatic alignment based on board size to eliminate pad offset issues.
DimensionsSurface FinishENIG. Thickness: 1u" / 2u"ENIG deposits a nickel-gold coating on exposed pads to prevent oxidation.
DimensionsThickness with StiffenerThickness with Stiffener = FPC Thickness + Stiffener ThicknessAsk about PI stiffener thickness
DimensionsFPC Thickness Tolerance

1. Area with stiffener thickness ≤ 0.3 mm: ±0.05 mm

2. Area with stiffener thickness between 0.3-1.0 mm (including 1.0 mm): ±0.1 mm

3. Area with stiffener thickness above 1.0 mm: ±10%

4. Gold finger area: ±0.03 mm

Additional tolerance exists for stiffeners. Thicker stiffeners have larger tolerances.
HolesHole Diameter0.1-6.5 mmThe recommended maximum diameter for PTHs is 5 mm, if bigger may cause risks to production
HolesDiameter Tolerance±0.08 mmExample: A 1.00 mm designed diameter is allowed to yield any physical diameter between 0.92-1.08 mm.
HolesMinimum Plated Slot0.50 mmmin plated slot width
HolesMinimum Non-Plated SlotNot limitedAt least 0.2 mm copper clearance is required around non-plated slots.
HolesCastellated Holes

Castellated holes are plated half-holes on the edge of an FPC. Most often used for press-soldered connectors.

① Castellated hole diameter: ≥ 0.3 mm

② Castellated hole to board edge: ≥ 0.5 mm

③ Castellated hole to hole: ≥ 0.4 mm

fpc castellated hole specs
HolesMin. Via hole size/diameter

①Regular: 0.3mm/0.55mm

②Extreme for 2-layer: 0.10mm/0.3mm (extra cost required)

③Extreme for 4-layer: 0.15mm/0.35mm (extra cost required)

④Via diameter must be at least 0.2mm larger than via hole size, 0.25mm or above is better.

via hole diameter diagram
TracesAnnular Ring for PTH≥ 0.25 mm recommended, absolute limit: 0.18 mmpth annular ring specs
TracesMinimum Trace Width/Spacing (1 oz)

① 12 μm (0.33 oz) copper: 3/3 mil (absolute limit 2/2 mil – avoid if possible)

② 18 μm (0.5 oz) copper: 3.5/3.5 mil

③ 35 μm (1 oz) copper: 4/4 mil

These are regular capabilities. Contact customer support for custom capability requirements.

fpc trace width spacing
TracesTrace Width Tolerance±20%Example: A 0.10 mm designed trace width is allowed to yield any physical width between 0.08-0.12 mm.
TracesPad-to-Trace Clearance

① Via ring to trace: ≥ 0.1 mm (more whenever possible)

② Exposed pad to trace: ≥ 0.15 mm (more whenever possible)

pad to trace clearance
TracesNPTH to Copper Clearance≥ 0.20 mmThe clearance from an NPTH to traces, pads, and copper pours
TracesBGA

① BGA pad diameter: ≥ 0.25 mm

② BGA pad to trace clearance: ≥ 0.2 mm

fpc bga pad clearance
Coverlay / SoldermaskCoverlay ColorYellow / Black / White / TransparentYellow is recommended
Coverlay / SoldermaskCoverlay Opening

Coverlay expansion (one-sided): 0.1 mm

Coverlay opening to trace clearance: ≥ 0.15 mm (more whenever possible)

coverlay opening clearance
Coverlay / SoldermaskVia coveringRecommended to keep coverlay over vias
Coverlay / SoldermaskCoverlay Thickness

25µm dielectric thickness FPC:

① PI: 12.5μm, Adhesive: 15μm (on 1/3oz or 0.5oz copper)

② PI: 25μm, Adhesive: 25μm (on 1oz copper)

50µm dielectric thickness FPC: PI: 25μm, Adhesive: 25μm

Transparent FPC: PET: 25μm, Adhesive: 25μm

Note: white coverlay is usually 13-18μm thicker per side than yellow or black coverlay.

fpc coverlay thickness
Coverlay / SoldermaskMinimum solder bridge width0.5 mm minimum, i.e. solder bridge narrower than 0.5 mm will be removed. Contact customer support for any non-standard requirements.min solder bridge width
SilkscreenCharacter Height≥ 1mm (More in case of complex patterns or knock-out text)fpc silkscreen dimensions
SilkscreenCharacter Line Width≥ 0.15mm (Narrower lines do not print well)fpc silkscreen dimensions
SilkscreenCharacter to Pad Clearance≥ 0.15mm (Any silkscreen closer to a pad than this will be clipped)fpc silkscreen dimensions
FPC OutlineLaser Outline

① Copper to board edge ≥ 0.3mm

② Copper to slots ≥ 0.3mm

③ Outline tolerance: ±0.1 mm (±0.05 mm upon request)

fpc laser outline clearance
FPC OutlineGold Finger Pad to Board Edge Clearance0.2 mm. Gold fingers will be cut back if exceeding this clearance to avoid damage during laser cutting the outline. Castellated pads are exempt from this clearance.gold finger edge clearance
FPC OutlinePanels (See FPC Panel Design Guide)

① Spacing between boards is commonly 2 mm. For boards with metal stiffeners use 3 mm instead.

② Handling edges of width 5 mm required on all four sides. Copper pour is required on these edges, with 1 mm clearance around fiducials and 0.5 mm clearance around tooling holes.

③ Fiducials: 1 mm; tooling holes: 2 mm; Fiducial centre to board edge: 3.85 mm. Add four fiducials with one offset by 5 mm or more to aid orientation.

④ Support tab width: 0.7-1.0 mm

⑤ Maximum panel size: 234 × 490 mm

fpc panel design layout
StiffenersPI StiffenerThickness options: 0.1 mm, 0.15 mm, 0.20 mm, 0.225 mm, 0.25 mmPI stiffeners are most often used with gold finger connectors. For example if the connector needs to be 0.3 mm thick on a 0.11 mm FPC, a 0.225 mm stiffener thickness is most suitable.
StiffenersFR4 StiffenerThickness options: 0.1 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1.0 mm, 1.2 mm, 1.6 mm (bonding with adhesive under high temperature and pressure)FR4 is usually only used on low-end products because it is prone to chipping. Avoid if possible.
StiffenersStainless Steel StiffenerThickness options: 0.1 mm, 0.2 mm, 0.3 mmSteel stiffeners cost more but have excellent flatness and do not easily deform. This makes them good as support under SMD components. Note that since steel is slightly magnetic it should not be used with hall effect sensors or similar components.
Stiffeners3M Tape

3M9077 (0.05 mm thick; heat-resistant)

3M468 (0.13 mm thick; not heat-resistant)

tesa8854 (0.1mm thick; heat-resistant, good adhesion, recommended)

Usually used to secure FPCs after assembly
StiffenersEM Shielding Film18 μm thick, black. Helps lower EMC. The recommended practice is to add soldermask openings to electrically connect ground plane with the shield films.emi shielding film ground
Bend RadiusRecommended Minimum Bend Radius

Single layer: ≥ 6× total thickness

Multi-layer: ≥ 10× total thickness

Dynamic bending applications strongly recommend 1-2 layers with adhesive-less PI substrate.
Bend RadiusStatic vs Dynamic Bending

Static Bending: Smaller radius allowed (typically 6-10× thickness)

Dynamic Bending: Larger radius required (≥ 10-15× thickness recommended)

Static: Bent once or few times during assembly and remains in fixed shape. Suitable for most applications.

Dynamic: Repeated bending (thousands of cycles). Use 1-2 layers + adhesive-less PI for best lifespan. Avoid placing vias/pads in bend area.

Design ConsiderationsImpedance Calculation

Core polyimide εr: 3.3

Coverlay εr: 2.9

Core polyimide thickness: 25 μm / 50 μm

Impedance measurement and control are not yet supported. Traces are only controlled for width and the customer is responsible for choosing trace widths to achieve their impedance requirements. JLCPCB provides impedance reference line widths; ask about FPC impedance requirements.
Design ConsiderationsEasyEDA (Highly Recommended)EasyEDA supports a dedicated stiffener layer. The shape and thickness of stiffeners are set and embedded in the design document so they don't need to be entered manually when ordering. Get FPC design supporteasyeda stiffener setting
Design ConsiderationsOther EDA SoftwarePut annotations on its own layer. Include the outlines of the stiffeners and indicate material and thickness. This information is not automatically parsed so stiffener options need to be set manually when ordering. Make sure that annotation text does not overlap the board area.eda stiffener annotations
Design ConsiderationsOther Design ConstraintsSame requirements as rigid PCBs in terms of holes, traces, soldermask, and silkscreen.

PCB Assembly capabilities

PCB Assembly Technical Capabilities
FeaturesEconomic PCBAStandard PCBA
Assembly TypesSingle sided placement (SMT/Thru-hole)Single & double sided placement (SMT/Thru-hole)
PCB Layer2,4,6-layers1 - 32 layers
Thickness0.8mm - 1.6mmNo limit
Dimension

Single PCB Size: 10x10mm - 470x500mm

PCB Panel Size: 10x10mm - 250x250mm

Single PCB Size: 70x70mm - 460x500mm

PCB Panel Size: 70x70mm - 250x250mm

Order Volume2 - 50 pcs2 - 80000 pcs
Surface FinishLimited by specific options (Refer to the options for Economic PCBA in the table below)No limit
PCB ColorLimited by specific options (Refer to the options for Economic PCBA in the table below)No limit
Delivery FormatSingle PCB, Panel with mouse bitesSingle PCB, Panel with mouse bites, Panel with V-cut
Layer StackupStandard stack-up only, special stack-up is not supportedAll stack-up
Gold Fingers/Castellated Holes/Edge PlatingNot SupportSupport
Edge RailsNot necessaryNecessary
FiducialsNot necessaryNecessary
Minimum Package04020201
Minimum IC Pin Spacing0.4mm0.35mm
Minimum BGA Spacing0.5mm (center to center)0.3mm (center to center)
Reflow temperature255+/-5 °C (not adjustable)240+/-5 °C
SPINoYes
AOIYesYes
Visual InspectionYesYes
X-ray InspectionYes (only for certain parts, such as BGA)Yes (only for certain parts, such as BGA)
Build time1 - 3 days≥ 4 days
PCB Specs for Economic PCB Assembly
LayerThickness(mm)ColorSurface FinishQty(pcs)
0.8Green

Lead-Free: HASL

Leaded: HASL

2-30
1Green/Black

Lead-Free: HASL

Leaded: HASL

2-30
1.2Green/Black

Lead-Free: HASL

Leaded: HASL

2-30
1.6Green

Lead-Free: HASL / ENIG

Leaded: HASL / ENIG

2-50
1.6Black

Lead-Free: HASL

Leaded: HASL

2-50
1.6Blue/Purple

Lead-Free: HASL

Leaded: HASL

5-30
1.6Red/WhiteLeaded: HASL5-30
1Green

Lead-Free: HASL

Leaded: HASL

2-30
1.2Green

Lead-Free: HASL

Leaded: HASL

2-50
1.6Green

Lead-Free: HASL / ENIG

Leaded: HASL / ENIG

2-50
1.6GreenENIG2-30

SMT Stencil capabilities

SMT Stencil Specifications
FeatureCapabilities
Stencil TypesFramework & Non-Framework
Stencil Material304 HTA stainless steel
Minimum Aperture Size>0.08mm
Cutting Tolerance±0.003mm
Cutting TechnologyPrecision Laser Cutting
Manufacturing CapabilitiesOver 30 laser cutting machines in operation
Stencil File FormatsGerber files (with solder paste layers), DXF
Thickness

Select by JLCPCB

Our engineers will select an appropriate thickness based on your design from the standard thickness.

Select by customer

If you wish to specify the thickness by yourself, please select 'Select by Customer'.

Standard thickness (no extra cost): 0.10 mm, 0.12 mm, 0.15 mm, 0.18 mm, 0.20 mm.

Special thickness (with extra cost): 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.08mm, 0.25mm, 0.3mm, 0.4mm, 0.5mm.

Dimensions

Non-Framework:

Standard size: 280x380mm - 700 × 600 mm

Custom size: You can customize any dimensions within 650*580mm.

Note: Any non-standard sizes, for example, 1:1 as PCB, need to choose custom size and input specific size.

Framework:

Minimum: 400*300 (Valid Area 240mm*140mm)

Square Max: 736 × 736 mm (Valid Area: 500 × 500 mm)

Rectangular Max: 1500 × 500 mm (Valid Area: 1300 × 320 mm)

Note: Valid Area is where the apertures can be open

Nano-CoatingAvailable for all types of stencils
Step StencilOnly available for stencils with framework
Ultrasonic-Resistant AdhesiveOnly available for stencils with framework
Stencil Side

4 options:

1. Top Only

2. Bottom Only

3. Top + Bottom (On Single Stencil)

4. Top + Bottom (On Separate Stencils)

Get a DIYIPCB stencil quote.

Stencil Process Type

2 options:

1. Solder Paste Stencil

2. Red Glue Stencil

Get a DIYIPCB stencil quote.

Polishing Process

3 Options:

1. Sanding

2. Etching Polish

3. Electropolishing (Ideal for ICs ≤ 0.5 mm pitch and BGA packages)

Get a DIYIPCB stencil quote.

Fiducials

3 options:

1. No Fiducial

2. Etched Through

3. Etched Half Into

Get a DIYIPCB stencil quote.

Stencil Package

Non-framework:

≤250×250 mm: Packed in a plastic bag with an air-shipping box.

>250×250 mm: Packed in a cardboard box and clamped with wooden boards.

Framework: Packed in a box, then clamped with wooden boards

Build Time

Fastest build time: 12 hours

Note: The final build time may vary based on the selected stencil specifications and order confirmation time.

Stencil Delivery

If you order a stencil together with PCBs, stencil size within 280mm × 280mm can be shipped together with the PCBs.

However, if you choose express shipping (e.g., DHL, FedEx), stencil size exceeding 280mm × 280mm will be shipped separately.