• AD7689: FAQ

    FAQ

  • AD7689 internal temperature sensor

    Q 

    I would like to know the conversion method of the temperature measurement using
    the internal temperature sensor in the AD7689.

    I have measured the folowing data:
    at -40 (cell) -> C73
    at +80 (cel)  -> 140C

    Using ext Vref  4.096, 16 bit data…

  • AD7689 digital interface timing

    Q 

    I double checked with spec that there is no timing graph except some simple
    text to descrip the modes of  "Reading/Writing During Conversion, Fast Hosts "
    and "Reading/Writing During Acquisition, Any Speed Hosts "

    Would you…

  • AD7689 and AD7949 disable internal clock

    Q 

    I'm wondering if the internal clocks in these devices are active only for the
    conversion or if it is possible to disable them using one of the operating
    modes?

     

    A 

    There is no internal clock for AD7689 and AD7949. You have to provide an
    external…

  • AD7689 unipolar differential pair problem

    Hello, everyone. I am trying to measure thermistor voltage to check the temperature.

    In this case, I have designed a circuit like the above one, and I connected 2 wires to AD7689's IN0 and IN1.

    The VTH(+) is connected with IN0 and VTH(-) is connected…

  • ad7689 使用问题

    我在使用ad7689时发现ad7689包输入电压抬高了1.5v，本来dcdc输出为5.1v装上ad7689就变为6.5v，还有我使用内部参考源4.096v，发现基准源不对，一直在跳变下面是我的原理图 ，

  • I am going to use the AD7689 in order to digitize 4...20 mA signals and temperature signals from various sensor

    Q 

    I am going to use the AD7689 in order to digitize 4...20 mA signals and
    temperature signals from various sensor. The reference voltage source will be
    an external 2.5V (AD441BRZ). The inputs will be driven by AD8628 and AD8231. As
    the positive…

  • Abou temperature drift of the internal reference of the AD7689

    Hi all,

    I am using AD7689 in my design.
    Please let me know if you have any information on the min and max values regarding the temperature drift of the internal reference.

    BestRegards,
    Takahiro

  • AD7689 unipolar differential pair problem

    Hello, everyone. I am trying to measure thermistor voltage to check the temperature.

    In this case, I have designed a circuit like the above one, and I connected 2 wires to AD7689's IN0 and IN1.

    The VTH(+) is connected with IN0 and VTH(-) is connected…

  • AD7689: PSRR much worse than in the datasheet

    Hello,

    under certain operating conditions we have some noise on the VCC +5V rail of the AD7689. Not pretty, but the ADC should be able to handle it.

    The AD7689 is supposed to have > 60 dBe of power supply rejection ratio up to 500 kHz. So much for theory…