FDC2214: Application questions

Shinya Sawamoto

Part Number: FDC2214
Other Parts Discussed in Thread: FDC1004, LDC1101, LDC1612, LDC1312

Hello team,

Let me ask if there is any good application note or recommendation design examples in the following use case.
1) I think the sensor input pair should be twist paired as far as possible to avoid unlike noise effect, but it there is a physical isolation to make it difficult like an attached image, is there any good use case example?
2) When the PCB mounted the FDC is battery powered and isolated to the host, is there any limitation or application notice?

Thanks in advance.
S.Sawamoto

over 4 years ago

0 John Miller - Sensing over 4 years ago

TI__Mastermind 37605 points

Sawamoto-san,

Thank you for your inquiry and your interest in TI devices.

We do not have any app notes dedicated to the application you describe.
I have included the FDC app notes and tech articles I know of in the table below

The success of the application will depend not only on the device, but also on the system it will be working in.
It is difficult to make recommendations without knowing more about the overall system.

One factor to consider is the FDC2214 maximum sensor capacitance is 250nF, which will include the capacitance of the twisted pairs in your application.
In this case, the capacitance of the twisted pairs may be a limiting factor, but you will need to confirm that.

Also, long connection wires may make the application susceptible to EMI, which could be difficult to manage.
That is why we recommend the FDC1004, because it has an active shield driver,

Please let me know if you have any questions.

Common Inductive and Capacitive Sensing Applications	http://www.ti.com/lit/pdf/slya048
Capacitive Sensing: Out-of-Phase Liquid Level Technique	https://www.ti.com/lit/pdf/snoa925
Capacitive Sensing: Ins and Outs of Active Shielding	https://www.ti.com/lit/pdf/snoa926
FDC1004: Basics of Capacitive Sensing and Applications	https://www.ti.com/lit/pdf/snoa927
Capacitive Proximity Sensing Using the FDC1004	https://www.ti.com/lit/pdf/snoa928
Liquid Level Sensing with the Immersive Straw Approach	https://www.ti.com/lit/pdf/snoa934
Capacitive Sensing: Direct vs Remote Liquid-Level Sensing Performance Analysis	https://www.ti.com/lit/pdf/snoa935
Measuring Rp of an L-C Sensor for Inductive Sensing	https://www.ti.com/lit/pdf/snoa936
Derivative Integration Algorithm for Proximity Sensing	https://www.ti.com/lit/pdf/snoa939
Capacitive Proximity Sensing Using FDC2x1y	https://www.ti.com/lit/pdf/snoa940
Power Reduction Techniques for the FDC2214/2212/2114/2112 in Capacitive Sensing Applications	https://www.ti.com/lit/pdf/snoa943
Optimizing L Measurement Resolution for the LDC161x and LDC1101	https://www.ti.com/lit/pdf/snoa944
Setting LDC1312/4, LDC1612/4, and LDC1101 Sensor Drive Configuration	https://www.ti.com/lit/pdf/snoa950
Ground Shifting in Capacitive Sensing Applications	https://www.ti.com/lit/pdf/snoa952
How to Calibrate FDC1004 for Liquid Level Sensing Applications	https://www.ti.com/lit/pdf/snoa958

Tech Articles/Blogs
Capacitive sensing: simple algorithm for proximity sensing	https://e2e.ti.com/BLOGS_/B/ANALOGWIRE/ARCHIVE/2015/11/23/CAPACITIVE-SENSING-SIMPLE-ALGORITHM-FOR-PROXIMITY-SENSING
Capacitive sensing: which architecture should you choose?	https://e2e.ti.com/blogs_/b/analogwire/archive/2015/10/20/capacitive-sensing-which-architecture-should-you-choose
What are you sensing? Active shielding for capacitive sensing, part 1	https://e2e.ti.com/blogs_/b/analogwire/archive/2015/02/18/what-are-you-sensing-active-shielding-for-capacitive-sensing_2c00_-part-1?DCMP=awire&HQS=tlead-sensing-ways-capsense-awire-20150225-20150218-en
What are you sensing? Active shielding for capacitive sensing, part 2	https://e2e.ti.com/blogs_/b/analogwire/archive/2015/02/25/capacitive-sensing-the-ins-and-outs-of-active-shielding-part-2

0 Shinya Sawamoto over 4 years ago in reply to John Miller - Sensing

TI__Expert 5285 points

Hi John,

I really appreciate your kind information.
They are really helpful!

Thanks,
S.Sawamoto

Sensors

Sensors forum

FDC2214: Application questions