TPS7B7701-Q1: Question about Thermal resistance and R(outxoff)

tateo yamashiro

Part Number: TPS7B7701-Q1

Hi,

We got questions from customer about TPS7B7701-Q1.
Could you help us?

[Question]
- What is the baord condition of the thermal resistance? We are thinking it is JESD 51-7 standard. But we would like to confirm the condition.

   Board size: 76.2x114.3x1.6mm ?
   Layer size: 74.2x74.2mm ?
   Layer Count: ?
   Through-hole Count: ?

- How much is the variation of R(outxoff)? They would like to know the minimum and maximum value. They don't need gurantee.

Best Regards,
tateo

over 6 years ago

0 David Hopkins over 6 years ago

TI__Expert 8905 points

Hi Tateo,

It is based on the JEDEC high-K board profile. As this is a standard always refer to the latest specification for more details. The information you are asking for is covered in page 18 to 19 of JEDEC 51-12.01.

https://www.jedec.org/system/files/docs/JESD51-12-01.pdf

Resistor variation for an on-chip resistor typically is quite large - if you need an accurate output pull-down resistance I would advise using an external resistor with a much better tolerance and sizing it to be much smaller then the internal resistor typical value.

-David

0 tateo yamashiro over 6 years ago in reply to David Hopkins

Guru 10890 points

Hi, Thank you for your reply.

I can't access your link of JEDEC 51-12.01. Could you attach your pdf file on this thread?

They need the variation of R(outx-off) for their internal review. They don't need an accurate of resistor. Could you provide min and max value?

Best Regards,
tateo

0 tateo yamashiro over 6 years ago in reply to David Hopkins

Guru 10890 points

Hi, Is there any update on that? I would appreciate it if you could give us your feedback.

Best Regards,

tateo

0 tateo yamashiro over 6 years ago in reply to David Hopkins

Guru 10890 points

Hi, I could see the file of JEDEC 51-12.01. I have confirmed board dimension and material. But I couldn't confirm layer count. Could you provide the information of layer count?

Best Regards,
tateo

0 Mark Sellers over 6 years ago in reply to tateo yamashiro

TI__Expert 6825 points

Hi Tateo,

Sorry for the confusion of the link sent earlier. Here is a link that descibes how we are doing our thermal numbers:
www.ti.com/.../spra953c.pdf

We do not have a maximum number for this resistor, but it will vary by approximately 20%.

Hope this helps.

Regards,
Mark

0 tateo yamashiro over 6 years ago in reply to Mark Sellers

Guru 10890 points

Hi, Thank you for your reply. Which is the layer count of the test board, 1S or 2S2P?

Best Regards,
tateo

0 Mark Sellers over 6 years ago in reply to tateo yamashiro

TI__Expert 6825 points

Hi Tateo,

For the thermal models the boards are 2S2P for HighK.

For our EVMs we usually have 1s1p (occasionally there is a trace on the power plane though).

Regards,
Mark

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TPS7B7701-Q1: Question about Thermal resistance and R(outxoff)