PGA900: What purpose does it have the VBRGN?

Hayashi

Expert 1840 points

Part Number: PGA900

Hi teams,

I have a question about PGA900's pin of VBRGN.

What is purpose that the PGA900 purposely is built the pin of VBRGN?

Best regards

Hayashi

over 7 years ago

0 Scott Cummins over 7 years ago

TI__Mastermind 31655 points

Hello,

It is internally connected to ground, so it is basically just another place that the VBRG negative can be connected.

Regards,

0 Hayashi over 7 years ago in reply to Scott Cummins

Expert 1840 points

Hello, Scott san
Thank you for your reply.

So, we just wanted to know why VBRG negative is connected outside of the board.
There must be some kind of reason right?
As our customer needs the internal block info, PLEASE send us what you got.

Best regards.
Hayashi

0 Hayashi over 7 years ago in reply to Hayashi

Expert 1840 points

Hello, Scott san

How is this situation?

Best regards.
Hayashi

0 Hayashi over 7 years ago in reply to Hayashi

Expert 1840 points

Hi, Scott san

I'm waiting for your reply.
How is that matter going?

Best regards.
Hayashi

0 Scott Cummins over 7 years ago in reply to Hayashi

TI__Mastermind 31655 points

Hello,

Internally the resistance to GND is matched to the resistance from the internal 2.5V supply to the VBRGP pin.

Regards,

0 Hayashi over 7 years ago in reply to Scott Cummins

Expert 1840 points

Hi Scott san

Thank you for your reply.

We just want to know "HOW" VBRGN of PGA900 is connected to ground internally.
SO that, I'm worried that the crosstalk from other GND(pin of AVSS,DVSS,GND) would affect this VBRGN pin.

Best regards.
Hayashi

0 Hayashi over 7 years ago in reply to Hayashi

Expert 1840 points

Hello, Scott san

How is this situation?

Best regards.
Hayashi

0 Scott Cummins over 7 years ago in reply to Hayashi

TI__Mastermind 31655 points

Hello,

I cannot share the specifics of the internal structure beyond what I have already explained. Any disturbances to the analog ground will also cause a disturbance to the VBGN pin. I would not consider this "crosstalk" since VBRGN is effectively shorted to the analog ground and is not really a separate node.

Regards,

Data converters

Data converters forum

PGA900: What purpose does it have the VBRGN?