Connector silk screen

[Rajinder1268]

Hi all,
I have created the footprint for the following connector based on the datasheet land pattern.

WF12504-01200 SHENZHEN ATOM TECH | C479978 - LCSC Electronics

WF12504-01200 SHENZHEN ATOM TECH $0.0971 - 1x4P 4P 1 1.25mm 4 -25℃~+85℃ 1A Surface Mount，Right Angle SMD,P=1.25mm,Surface Mount，Right Angle Wire To Board Connector ROHS datasheet, price, inventory C479978

www.lcsc.com

Note: I have also attached the datasheet.

I have a problem in creating the size of the silkscreen around the connector, particularly where the edge of the connector would be relative to the edge of my PCB.
Can anyone help me to obtain these dimensions from the datasheet.

I need to know how to calculate the rough size of the outer housing of the connector to aid in placing other nearby parts and to the PCB edge.

Thanks in advance
Raj

 

[barry]

Really? The dimensions are right there: E x 3.45.

You should probably take a course or something on reading mechanical drawings.

 

[Rajinder1268]

Really? The dimensions are right there: E x 3.45.

You should probably take a course or something on reading mechanical drawings.

Hi Barry,
I think you may be right about the mechanical drawing course, I really am not good at reading mechanical diagrams.
My issue is where to start the silk screen marking and where the connector edge will be in relation to the PCB edge.
I will have a go at it and post my footprint + silk screen.

Thanks in advance.

 

[barry]

Those are two separate issues. The silkscreen is not necessarily an exact outline of the part (it can be). There is also something called a “courtyard” associated with PCB layout; that’s the area around a component where other components are forbidden. PCB layout packages often have a Courtyard layer.

As far as where the connector is in relation to the board edge, that really depends on the connector; some need to be flush, others don’t care. You can also have a mechanical layer associated with a footprint to aid exactly placing the component.

 

[Rajinder1268]

Those are two separate issues. The silkscreen is not necessarily an exact outline of the part (it can be). There is also something called a “courtyard” associated with PCB layout; that’s the area around a component where other components are forbidden. PCB layout packages often have a Courtyard layer.

As far as where the connector is in relation to the board edge, that really depends on the connector; some need to be flush, others don’t care. You can also have a mechanical layer associated with a footprint to aid exactly placing the component.

Hi Barry,
Thanks for your reply. Some manufacturers have on their connector data sheets a board edge marking, this makes it easier to create the footprint. I am aware of the courtyard, usually it indicates that you do not place components in close proximity to each other.

Perhaps my initial question was not clear. I want to position the connector so that it sits flush with my PCB edge. From the mechanical drawings could you assist where this would be?

Best regards
Raj

 

[barry]

You can see that the body of the connector is 4.4mm from front to the point where the 0.85mm pins come out, the exact configuration of the pins Is not clear. But if it was me, I’d assume the middle of the pin sits in the middle of the pad, so the front edge of the connector would 4.4 + 0.85/2 mm from the center of the pad.

 

[FvM]

This is a wire-to-board connector. It simply has no dedicated PCB edge position, other than an edge mounted board-to-board connector. You might e.g. want to align the connector housing with the PCB edge, set it back or even let it hang over.

--- Updated Nov 24, 2021 ---

In practice, the relative position to board edge is constraint by the SMD pad to board contour clearance design rule.

--- Updated Nov 24, 2021 ---

These days, you'll prefer to get 2D or 3D mechanical data from manufacturer and import it to PCB tool.