Layer count

1,2,4,6 layers

The number of copper layers in the board.

Controlled ImpedanceMaterial

4/6 layer, default layer stack-up

Controlled Impedance PCB Layer Stackup

siampcb Impedance Calculator

Material

FR-4

FR-4 Standard Tg 130-140/ Tg 155

Dielectric constant

4.5(double-side PCB)

7628 structure 4.6

2313 structure 4.05

2116 structure 4.25

Max. Dimension

400x500mm

The maximum dimension siampcb can accept

Dimension Tolerance

±0.2mm

±0.2mm for CNC routing, and ±0.4mm for V-scoring

Board Thickness

0.4/0.6/0.8/1.0/1.2/1.6/2.0mm

The thickness of finished board.

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)

± 0.1mm

e.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

1 oz/2 oz (35um/75um)

Finished copper weight of outer layer is 1oz or 2oz.

Finished Inner Layer Copper

0.5 oz (17um)

Finished copper weight of inner layer is 0.5oz only.

Drill Hole Size (Mechanical)

0.20mm- 6.30mm

Min. drill size is 0.20mm. Max. drill size is 6.30mm.

Drill Hole Size Tolerance

+0.13/-0.08mm

e.g. for the 0.6mm hole size, the finished hole

size between 0.52mm to 0.73mm is acceptable.

Blind/Buried Vias

Don’t support

Currently we don't support Blind/Buried Vias,

only make through holes.

Min. Via hole size

0.2mm

For Single&Double Layer PCB, the minimum via hole

size is 0.3mm;For Multi Layer PCB, the minimum via

hole size is 0.2mm

Min. Via diameter

0.45mm

For Single&Double Layer PCB, the minimum

Via diameter is 0.6mm;For Multi Layer PCB, the minimum via diameter is 0.45mm.

PTH hole Size

0.20mm - 6.35mm

The annular ring size will be enlarged to 0.15mm in production.

Pad Size

0.70mm- 6.35mm

The pad hole size will be enlarged 0.15mm in production.

Min. Non-plated holes

0.50mm

The minimum NPTH dimension is 0.50mm, Please add the NPTH in the mechanical layer or keep out layer.

Min. Plated Slots

0.65mm

The minimum plated slot width is 0.65mm, which is drawn with a pad.

Min. Non-Plated Slots

1.0mm

The minimum Non-Plated Slot Width is 1.0mm,

please draw the slot outline in the mechanical layer(GML or GKO)

Min. Castellated Holes

0.60mm

The minimum diameter of castellated holes is 0.60mm.

Hole size Tolerance (Plated)

+0.13mm/-0.08mm

e.g. for the 1.00mm Plated hole, the finished hole

size between 0.92mm to 1.13mm is acceptable.

Hole size Tolerance (Non-Plated)

±0.2mm

e.g. for the 1.00mm Non-Plated hole, the finished hole

size between 0.80mm to 1.20mm is acceptable.

Rectangle Hole/Slot

Don’t support

We don't make rectangle hole/slot,the rectangle

hole/slot will be made as round or oval hole/slot by default.

1oz Copper

0.13mm

0.3mm

2oz Copper

0.2mm

0.3mm

Features

Capabilities

Patterns

Hole to hole clearance(Different nets)

0.5mm

Via to Via clearance(Same nets)

0.254mm

Pad to Pad clearance(Pad without hole, Different nets)

0.127mm

Pad to Pad clearance(Pad with hole, Different nets)

0.5mm

Via to Track

0.254mm

PTH to Track

0.33mm

NPTH to Track

0.254mm

Pad to Track

0.2mm

H/HOZ (Inner layer)

5mil (0.127mm)

5mil (0.127mm)

1oz (Outer layer)

1/2 layers: 5mil (0.127mm)

4/6 layers: 3.5mil(0.09mm)

1/2 layers: 5mil (0.127mm)

4/6 layers: 3.5mil(0.09mm)

2oz (Outer layer)

8mil (0.2mm)

8mil (0.2mm)

1/2 layers

0.4 mm

0.127mm

4/6 layers

0.25 mm

0.127mm

Features

Capabilities

Notes

Patterns

Solder mask opening/ expansion

0.05mm

The solder mask should have a minimum of a 0.05 mm "growth/mask opening" around the pad to allow for any mis-registration.

Solder bridge

0.2mm(green)

0.254mm(other colors)

To have solder mask bridge, the spacing between copper pads edge must be 0.2mm (8mils) or more.

Solder mask color

green, red, yellow, blue, white, and black.

We use LPI (Liquid Photo Imageable) solder mask.

It is the most common type of mask used today.

Solder mask dielectric constant

3.8

Solder mask thickness

10-15UM

Features

Capabilities

Notes

Patterns

Minimum Line Width

6 mil (0.153mm)

Characters width less than 6mil(0.153mm) will be unidentifiable.

Minimum text height

32 mil (0.8mm)

Characters height less than 32mil(0.8mm) will be unidentifiable.

Character width to height ratio

1:6

The preferred ratio of width to height is 1:6.

Pad To Silkscreen

0.15mm

The Minimum Distance Between Pad and Silkscreen is 0.15mm.

Features

Capabilities

Notes

Patterns

Trace to Outline

0.2mm

Ships as individual board(Rounting):Trace to Outline≥0.2mm

Trace to V-cut line

0.4mm

Ship as panel with V-scoring: Trace to V-cut line≥0.4mm

Panelization without space

0mm

The space between boards is 0mm.

Panelization with space

2mm

Make sure the space between boards should be ≥2mm,otherwise it will be hard to process for rounding.

Panelized Round board

≥20mmx20mm

The single round board size should be≥20mmx20mm.

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

Panelized castellated holes board

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

The distance between castellated hole and board corner should be larger than 4mm.

Recommended diameter of stamp hole is 0.5mm-0.8mm;

Recommended distance between the two stamp holes is 0.2-0.3mm

Min. Width of Breakaway Tab

4mm

The minimum width of breakaway tab is 4mm. For breakaway with mouse-bites, the minimum width is 5mm.

Min. Edge Rails

4mm

If choosing panel by JLCPCB, we will add 5mm

edge rails on both sides by default.