LM73 IC Interface issue

6406.Issue with I2C Communication with LM73.docDear All,

Hi I am using Temperature sensing IC LM73 for temperature sensing application.

I have following issues:

1. The marking on LM73 IC is T730. But no marking or notch available indicating IC pin 1. So I have selected the pin which is to the left of start of marking T730 on IC.

2. I am facing problem with communication with IC is it so that I have made wrong connections as per the nomenclature I have followed as discussed in point 1. The reason is the IC is not acknowledging the address/data sent.


2 Replies

  • Hi Shrikant,

    Sorry about the delay in reply to your request.

    If the part does not ACK the address it will also not ACK any other frame following it.

    Based on your description you do have pin 1 right but to make sure I've attached a photo for you to look at. Pin 1 is at the bottom of the T. You can also see a indentation in the plastic as a 1 designator, it runs the length of the package.

    Also if you do have it inserted right - you may want to try 1001101 as a device address - just in case the parts are marked incorrectly.

    Let me know how it turns out.

    Take care,

    Precision Systems Applications
    Silicon Valley Analog (formerly National Semi)
    Texas Instruments.4530.LM73-pin1.zip




    Temperature Sensor Applications
    Texas Instruments