• State
  • Locked Locked
  • Replies 3 replies
  • Subscribers 30 subscribers
  • Views 740 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

LDC1000's ODR

Thomas Lehner
Prodigy 30 points
Other Parts Discussed in Thread: LDC1101

Hello TI Team!

On page 5 of the LDC1000's datasheet (electrical characteristics) the min. and max response times of the sensor are given with (Responsetime x 1/f_sensor).

On page 21 the sensor's ODR is calculated using Responsetime/3.

What is the difference between min/max responsetime and ODR?

On page 7 (timing requirements) what is the t_IAG (Inter Access-Gap) or where can I find it in the diagram?

Thank you,

Regards, Thomas

  • 0
    TI__Genius 14270 points

    Hello Thomas,

    The conversion interval is RESPONSE_TIME / (3 * fsensor), which is the ODR (output data rate). Response time is related to the impulse response time; it is effectively a device configuration which sets the conversion interval.

    The t_IAG is the minimum time that CSB must be held high before a new SPI transaction.

    Regards,

    ChrisO

  • 0 in reply to Chris Oberhauser66
    Prodigy 30 points

    Thank you for your fast reply ChrisO!

    Your answer leads me to my next question:

    With fastest possible ODR (12,8µs) and 48bit to read, it'll need about 266ns per bit.

    So data read is already pritty close to the maximum f_SCLK of 250ns (4MHz).

    Is it actually possible to deliver every measured value?

  • 0 in reply to Thomas Lehner
    TI__Genius 14270 points

    Hello Thomas,


    Yes, it is fast enough to retrieve all of the data; you are correct in that it is rather tight timing. If you are using a sensor with 5+MHz, you may consider looking at the LDC1101, which is a faster part - it can go up to 10MHz for the sensor, and has an 8MHz SPI bus.

    Regards,

    ChrisO