How do I reduce the lengths of the pads using kicad footprint generator script

[JonRussell00]

Hi,

I am trying to create a new footprint for my device. I need a W-QFN2020-12 footprint.

I worked out how to use the kicad footprint generator script and this is my yml file below.

It works, and the footprint looks roughly correct, but the SMD pads extend a long way outside the device and I want to reduce that.
The pad on the chip is 0.3mm (which is the parameter I have used in the YML File), the datasheet says the PCB pad should be 0.5mm, but the script is generating pads 0.65mm.

Is there a parameter that can define the PCB pad to be a certain length?

Thanks.

Jon.

WQFN-12_2.0x2.0mm_P0.4mm:
device_type: ‘WQFN’
manufacturer: ‘Diodes’
part_number: ‘PAM8904E’
size_source: ‘https://www.diodes.com/assets/Datasheets/PAM8904E.pdf’
ipc_class: ‘qfn’ # ‘qfn_pull_back’

body_size_x:
nominal: 2.0
tolerance: 0.05
body_size_y:
nominal: 2.0
tolerance: 0.05
overall_height:
nominal: 0.75
tolerance: 0.05

lead_width:
nominal: 0.2
tolerance: 0.05
lead_len:
nominal: 0.3
tolerance: 0.05

pitch: 0.4
num_pins_x: 3
num_pins_y: 3

EP_size_x:
nominal: 1.0
tolerance: 0
EP_size_y:
nominal: 1.0
tolerance: 0
EP_num_paste_pads: [2, 2]

I hereby certify that I am not simply asking someone else to design a footprint for me.

This is an auto-generated message that is in place on the “footprints” section of the KiCad.info forum. If I remove it and ask for a footprint to be designed anyway, I understand that I will be subject to forum members telling me to go design my own footprint or referring me to a 3rd party footprint site.

[Aris_Kimi]

Hello,

As a first step i would like to suggest to try and adjust the density level of the generator.

From the generator’s docs, you can use --density: IPC density level (L,N,M) (default=N).

If this doesn’t work for you, then just enter custom values that cover your needs.

The generator output is according to the IPC norms, it will probably never match a datasheet’s suggestion.

(to be honest, I tend to trust the generator more…)

Best regards,
Aristeidis

[retiredfeline]

Don’t the length and offset parameters work for you?