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.

TMP117: Did we have any suggestion for skin contact material on human health device?

Part Number: TMP117
Other Parts Discussed in Thread: TMP116METER-EVM

Hi Sir,

Our customer would like to design our TMP117 for human health device which would contact human skin and get the tempature measurement.

Here got 3 question would need your support:

1. Did we have any suggestion for the skin contact material? If so, could you please provide the suggestion or vendor brand? 

2. Customer mentioned the material of skin contact with "polymer polymer", is it the recommended material? If so, did we have any suggestion manufacturer?

3. Regarding the placement of components,it should be plus if TMP117 can be far away from the heat source of the system. But if they are difficult to achieve due to the size of the device, what would we recommended? Any other comments or experience sharing for this kind of limited space device?

Looking forward to hearing from your comments.

Thanks,

George

  • Hi George,

    Thank you for your post.

    George Liu1 said:

    1. Did we have any suggestion for the skin contact material? If so, could you please provide the suggestion or vendor brand?

    The only material recommendation we can really give is to use a non-oxidizing, bio-compatible material such as stainless steel. We are happy to review any designs they come up with as well. 

    George Liu1 said:
    2. Customer mentioned the material of skin contact with "polymer polymer", is it the recommended material? If so, did we have any suggestion manufacturer?

    I'm not sure what they mean by "polymer polymer", can you find more information about this material? In general the ideal materials for this purpose have a good thermal conductivity, and can be designed into a small contact or as a very thin layer. 

    George Liu1 said:
    3. Regarding the placement of components,it should be plus if TMP117 can be far away from the heat source of the system. But if they are difficult to achieve due to the size of the device, what would we recommended? Any other comments or experience sharing for this kind of limited space device?

    They should still try to provide as much distance as they can given their board size. In addition to that, they should also include a cutout around the device (see TMP116METER-EVM for an example). This Application report provides some details about thermal conduction and the reasoning behind some of our layout recommendations.

    Best Regards,
    Brandon Fisher

  • Thank you Sir, I got one more question.

    Did our TMP117 got any self test method/procedure and the test spec/criteria?

    George

  • Hi George,

    The TMP117 does not have a self-test procedure. If you wanted to check its accuracy after assembly it would have to be compared to an external reference. At this level of accuracy comparisons also have to be done in an extremely stable temperature environment such as a stirred liquid bath. 

    To check its communication the master could just send an I2C command (perhaps a read of the device id register) and verify that the TMP117 responded correctly. 

    Best Regards,
    Brandon Fisher