• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 465 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.

FDC1004: how to connect shield pin

Art Mecina
Genius 16655 points
Part Number: FDC1004

Hello Guys,

Good day.

Our customer have the following inquiries.

I'm using the FDC1004 and would like to know how to connect the Shield pin. Is it connected to a shield wire around the Cin pin or is it actually connected to the Cin pin?


In addition, should I use single ended mode or differential mode in the case we have two co-planar conductors?

Thanks and regards,

Art

  • 0
    TI__Mastermind 40295 points

    Art,

    The shield (SHLD1, SHLD2) is usually connected to a a separate trace and/or a conductive sheet that parallels a CIN trace and flat sensor.
    The SHLDx is driven with the same waveform as the Cin pin, so the CINx node and shield are at the same voltage so the mutual capacitance between the SHLD and CIN has no effect on the sensor readings. At the same time, the SHLD attenuates the impact of EMI on the CIN sensor.

    If you have two co-planar sensors that are meant to share in the detection of a common target, then the differential configuration is probably best.
    If the two conductors are detecting different things - or if you want to have some kind of redundancy while detecting the same thing - the single-ended mode might be best.

    Regards,
    John