LM8330: Simple Layout with shorten pins

Steffen Dase

Part Number: LM8330

Hi,

I like to use the LM8330 with only 4 columns and 3 rows. I dont like to use micro vias and would therefore shorten the pins C3, B3, B4, B5 to route the GND potential to C3 and D3, D4, E5 to route the 3V3 VCC.

Is this possible or does this have side effects?

over 2 years ago

0 Eric Hackett over 2 years ago

TI__Guru 68212 points

Steffen,

Just to make sure I understand, you want to connect B3, B4, and B5 all to C3 for the GND net, and D3 and E5 to D4 for the VCC potential? Where will the GND connection for C3 on the board be, just the copper on the top layer? Are you not using any vias at all, or do you just want to limit the use of vias?

Regards,

Eric Hackett

0 Steffen Dase over 2 years ago

Prodigy 155 points

Hi Eric,

yes, I like to use only normally drilled vias, instead of laser drilled vias, to keep for my simple board the costs lower. Therefore it was my idea, to connect the inner pads with the outer not used pads for a fanout. With this I have no need for any vias.

Best regards

Steffen

0 Eric Hackett over 2 years ago in reply to Steffen Dase

TI__Guru 68212 points

Steffen,

This should work, I would just worry about the ground return path being limited to just one layer. But if the amount of current being drawn is relatively low, this may be okay. Is there a way you can share an example of how the layout would look?

Regards,

Eric Hackett

0 Steffen Dase over 2 years ago in reply to Eric Hackett

Prodigy 155 points

Hi Eric,

please see the pictures below for schematic and layout.

0 Eric Hackett over 2 years ago in reply to Steffen Dase

TI__Guru 68212 points

Thank you for the image, this helps me understand a lot better. The GND via in the copper from the GND pins underneath the device, is this via'd down to another GND layer? If so this will work fine. And the 3.3V rail looks good to me too.

Regards,

Eric Hackett

Interface

Interface forum

LM8330: Simple Layout with shorten pins