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LDC1612: Flat sensor coil over round surface

Part Number: LDC1612

Hey guys,

Im using the LDC1612 to sense an aluminum tape triangle over a a plastic cylinder, the sensor coil is flat. The plastic Cylinder rotates over locking teeth so each "tooth" is supposed to be a certain part of the aluminum triangle, and I am only using one channel (one coil).

A triangle similar to the one below, but the aluminum metal triangle with the dx wrapped around on a plastic cylinder

Is the use case of using a coil to sense a aluminum triangle over a cylinder not recommended?

Could I expect similar values over multiple units, with the aluminum triangle not being flat?

EDIT:
I notice in my testing, if I power the sensor on with the skinny end of the triangle on the coil and move it in steps to the thickest part I get significant difference in results than when I power the sensor on starting with the thickest part on the coil and move it to the skinniest.

This is with AUTO_AMP_DIS disabled


  • Drawing of cylinder with triangle

  • Your design will work but would have lower sensitivity. Our sensors receive the greatest response with a flat target or one that covers the sensor completely. With round/cylindrical targets, you may consider a different orientation for the target and sensor or using a flex sensor that wraps around the cylinder. Refer to Target Size Matters for more information on this.

    In order to ensure repeatability from system to system, you would need to consider the effects of variations in sensor-to-metal spacing, mechanical tilt, and wobble and make sure these factors are well-controlled.

    Best,

    Jiashow