TPS2595: The exposed pad

Shuji Ishiwata

Part Number: TPS2595

Tool/software:

Hi All,

I have a question about the TPS259533.

Is the PAD connected to GND internally?
The NAME is GND, but when I checked the continuity between the GND terminal and the PAD on the IC alone, it was not connected.
Please reply to confirm.

Best Regards,
Ishiwata

11 months ago

0 Arush Gupta 11 months ago

TI__Mastermind 38335 points

Hi Ishiwata-san,

Yes, they should be internally shorted. Are you seeing some impedance between them?

Best Regards,
Arush

0 Shuji Ishiwata 10 months ago in reply to Arush Gupta

Mastermind 7755 points

Hi Arush-san,

Thank you for your reply.

A customer reported that the resistance between the PAD and GND is about 1.1MΩ to 1.6MΩ.
It seems like there is almost no connection, so what is the normal resistance?

Best Regards,
Ishiwata

0 Arush Gupta 10 months ago in reply to Shuji Ishiwata

TI__Mastermind 38335 points

Hi Ishiwata-san,

I will have to check this in lab. I will try to get back to you on this by eod.

Best regards,
Arush

0 Shuji Ishiwata 10 months ago in reply to Arush Gupta

Mastermind 7755 points

Hi Arush-san,

I am waiting for your reply.
Thank you.

Best Regards,
Ishiwata

0 Arush Gupta 10 months ago in reply to Shuji Ishiwata

TI__Mastermind 38335 points

Hi Ishiwata-san,

I have verified this (on bench and with team). Yes, there should be some impedance between the GND pin and the thermal pad.

Best Regards,
Arush

0 Shuji Ishiwata 10 months ago in reply to Arush Gupta

Mastermind 7755 points

Hi Arush-san,

Thank you for checking.

What was the impedance value?

Best Regards,
Ishiwata

0 Arush Gupta 10 months ago in reply to Shuji Ishiwata

TI__Mastermind 38335 points

Hi Ishiwata san,

On bench, I was also seeing resistance in very high range (order of MOhms).

Best regards,
Arush

0 Shuji Ishiwata 10 months ago in reply to Arush Gupta

Mastermind 7755 points

Hi Arush san,

Thank you for your reply.

I understand that the resistance is almost insulating.

I wouldn't say that the PAD and GND are connected.

Best Regards,
Ishiwata

0 Arush Gupta 10 months ago in reply to Shuji Ishiwata

TI__Mastermind 38335 points

Hi Ishiwata-san,

Yes, I also feel same now but it is still recommended to attach thermal pad to GND. Thermal pad provides other benefits like better thermals, board level reliability.

Best Regards,
Arush

0 Shuji Ishiwata 10 months ago in reply to Arush Gupta

Mastermind 7755 points

Hi Arush san,

Thank you for your reply.

If the thermal pad is not connected, are there any possible problems other than heat dissipation?

Best Regards,
Ishiwata

0 Arush Gupta 10 months ago in reply to Shuji Ishiwata

TI__Mastermind 38335 points

Hi Ishiwata-san,

As such there will be no electrical issue. You will get slightly bad thermal performance and board level reliability may reduce.

Best Regards,
Arush

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TPS2595: The exposed pad