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XTR105: Pad Connections

Part Number: XTR105

Hello All,

For the XTR105-DIE (Ref. Datasheet page 3 http://www.ti.com/lit/ds/symlink/xtr105-die.pdf) it shows pad number 3, 4, 5 and 6 as an “RG”.

For the XTR105 device (Ref. Datasheet page 2 http://www.ti.com/lit/ds/symlink/xtr105.pdf) doesn’t give a description of the above pad numbers.

 

Question: Are pads 3 and 4 connected internally or connected separately?

And what does “RG” stand for and should 3, 4, 5 and 6 all have the same "RG" description?

  • Daniel

    RG is the gain resistor. See the Functional Block Diagram on page 2 of the XTR105 data sheet.
    The die pad designations are a bit confusing, but these are positioned to be as close as possible to the lead frame pins they will be bonded to. Pads 3 and 4 are bonded to pin 3 on the lead frame and pads 4 and 5 are bonded to pin 4.

    Regards
    Dennis


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  • You realize you didn't answer the question?

    The question was "Are pads 3 and 4 connected together internally?".

    My guess is NOT. Probably one is connected to the RLIN resistor, and the other to the negative input of the op amp.

    Would you like to provide an answer to this question?

  • Wolf

    You are correct, they are not connected together. They are connected as shown in the Functional Block Diagram on page 2

    Regards
    Dennis
  • Let's try one more time.
    The Functional Block Diagram on page 2 does not show which pad of the die (3 or 4) is connected to RLIN and which one is connected to the op amp.
    Can I get a responsive answer to this question?
  • Wolf

    I see I have a typo in my original answer; pads 3 and 4 are bonded to pin 3...these are the pads that connect to Rlin.
    Pads 5 and 6 are bonded to Pin 4 on the leadframe and they provide the connection to the lower amp's inverting input.

    Regards
    Dennis
  • I see the other issue...pins 3 and 4 are eversed in the block diagram, so pads 5 and 6 go to Rlin.

    Regards
    Dennis
  • Please answer the following 7 questions. The questions are in regard to the pads 3, 4, 5, 6 of the die XTR105-DIE. Refer to the schematic of the XTR105 in a dual in line package, but ignore the pin numbers of the dual in line package. I need the connections to pads of the bare die.

    1. Are pads 3 and 4 connected together internally?

    2. Are pads 5 and 6 connected together internally?

    3. Which pad(s) is/are connected to the left side of resistor RLIN?

    4. Which pad(s) is/are connected to the negative input (-) of the left-top op amp?

    5. Which pad(s) is/are connected to the bottom end of the 100 µA current source?

    6. Which pad(s) is/are connected to the negative input (-) of the left-bottom op amp?

    7. Please provide a clear schematic showing the internal circuitry and the connections to the pads of the die XTR105-DIE, similar to the schematic and connections shown for the packaged device XTR105.

    It is very important for us to have this information.

    Thank you,

    Wolf Landmann

  • Wolf

    I'll answer as much as I can

    1. Are pads 3 and 4 connected together internally?
    No, they are Force and Sense connections:
    Die Pad 3 = Rg - Force
    Die Pad 4 = Rg - Sense

    2. Are pads 5 and 6 connected together internally?
    No, They are Force and Sense connections:
    Die Pad 5 = Rg + Force
    Die Pad 6 = Rg + Sense

    As far as your other questions, a detailed schematic of the die circuitry and the force and sense circuits fall under TI Proprietary Information and cannot be disclosed.

    Regards
    Dennis