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slotted pads on PCB

DesignSpark PCB makes it very easy to add slotted pads to your component footprint.
Here we examine the Allegro ACS770 current sensor https://uk.rs-online.com/web/p/current-sensor-ics/1709142

The footprint provided in the datasheet is:

Allegro ACS770 Footprint

The high current pads also have a non-symmetrical shape plus vias.

To illustrate the simplicity of creating a slotted pad we use a SnapEDA component model which has symmetrical pads but does not have a slot. As a note online component libraries from any source will often not include slots in a pad, the reason is that most ECAD software handles slots in a different manner and it is for you to customise as required.

source does not include slots

Examining the pad details in the Design Technology - Pads tab we can see it is defined as an oval pad 354 thou x177 thou with a 79 thou hole.
Select this pad and then click <Edit>

Edit Pad

You are now presented with the Pad Style window and can choose a shape for the hole!
Here we simply select the Rounded Rectangle for the hole and enter the required dimensions.

Pad Style Window

With the slots now in the pad, the updated pad can be saved and the component in the library will be updated as below.

Component Library

It is now ready for use in your design as shown in this simple example.

Now ready to use in your design

The Gerber plot files were produced for this simple PCB and checked in the Ucamco Online Reference Gerber Viewer.

Gerber Plots

Also, the validity of the Gerber and drill files were successfully confirmed with the EuroCircuits PCB Visualiser.

EuroCircuits Visualiser

The pad style/shape is selected as normal, if you then set a hole size this will be the default used as the slot width when generating a slot.
The Hole shape can be selected from the pull-down options and here we show them matching the pad shape.

Select hole shape from pull-down option

 

Technical Support for DesignSpark PCB