This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

  • TI Thinks Resolved

ADS7883: Junction to Case

Prodigy 30 points

Replies: 2

Views: 92

Part Number: ADS7883

How can it be (from other post):

The junction-to-case top thermal resistance for the ADS7883SBDBVT is 54.3 °C/W. The junction-to-board thermal resistance is 35.3 °C/W.

when thermal impedance in the data sheet is 295.2 °C/W?

  • This was the original question: e2e.ti.com/.../726647
  • In reply to Magnus Larsson54:

    Hello Magnus,

    The thermal impedance in the datasheet is the junction to ambient, which takes into account the thermal properties of the SOT23 package as well as the properties of a standard test PCB.  R-theta-ja is the least accurate number when used to predict thermal performance since there is a wide variation in actual PCB construction, but can be a good starting point, or figure of merit.

    Take a look at the following application note for a definition of the different thermal metrics.

    http://www.ti.com/lit/an/spra953c/spra953c.pdf

    Regards,
    Keith N.
    Precision ADC Applications

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.