TPS62148: GND solid pattern under inductor

Ryo Akashi

Part Number: TPS62148

Hello experts,

I got question about GND solid pattern under inductor from customer. Could you give me advice?

In generally, it is better to remove GND solid pattern under inductor because it may cause noise influence (e.g. eddy current?)

But, from the view of thermal performance, it is better to prepare GND solid pattern under inductor, I think.

If we use 4 layer PCB for TPS62148 design, could you give me comment which is better?

1) Remove GND solid pattern on L1, prepare GND solid pattern on L2/3/4

2) Remove GND solid pattern on L1/2/3, prepare GND solid pattern on L4 only

Also, if you know good app note or tech document, could you tell me?

I would appreciate if you would give me comment.

Thanks and best regards,

Ryo Akashi

over 4 years ago

0 Amod Vaze over 4 years ago

TI__Mastermind 23800 points

Hi Akashi-san,

Thanks for your question. With a shielded inductor for your design, the induced eddy current in the ground plane will be negligible. Also, it is good to have a continuous ground plane under the inductor for good shielding and better thermal performance. I found a post very similar to your question which may help: https://e2e.ti.com/support/power-management/f/196/t/538740

Regards,

Amod

0 Ryo Akashi over 4 years ago in reply to Amod Vaze

TI__Genius 9450 points

Hello Amod-san,

Thank you very much for your reply.

Ok, we understand ground plane under the inductor should not be problem of eddy current if we use shielded inductor.

Also, the post which you shared is helpful. Thank you.

Thnaks and best regards,

Ryo Akashi

Power management

Power management forum

TPS62148: GND solid pattern under inductor