FDC1004: Analog MUX on Sensor Inputs

user5065418

Part Number: FDC1004
Other Parts Discussed in Thread: TMUX1108,

Hi TI,

I'm working on a conceptual design for a proximity sensor application and had a question about potentially MUXing the CIN1 - CIN4 Inputs of of the FDC1004. I would like to use something like 16 to 24 different electrodes in my system all spaced out in a grid. Can I interface each of the CIN1 - CIN4 inputs of the FDC1004 to an analog 8:1 MUX like the TMUX1108? My electrodes would be connected to the S1 - S8 pins of the TMUX1108 and the D pin would be connected to a CINx pin of the FDC1004. Is this an acceptable application if I don't intend to sample all of my electrodes quickly? Are there any concerns I should have with interfacing the device with an analog MUX?

Thank you for your help!

Phil B

over 5 years ago

0 Kristin Jones93 over 5 years ago

TI__Genius 17440 points

Hi Phil,

Though we have not tried it in the past, I think using an analog MUX with the FDC1004 would be acceptable. You'll need to make sure that the MUX does not switch while a channel is being measured, so I'd make use of the FDC_CONF register (0x0C). You can use this register to disable repeat measurements and monitor when individual channel measurements have been completed.

If you're working on a proximity sensor application, you may find these two TI Designs helpful:

http://www.ti.com/tool/TIDA-00373

http://www.ti.com/tool/TIDA-00220

Best Regards,

0 user5065418 over 5 years ago in reply to Kristin Jones93

Prodigy 60 points

Hey Kristin,

Great! Really appreciate the fast response. Will look into the two reference designs you posted.

Have a good weekend,

Phil Beard

Sensors

Sensors forum

FDC1004: Analog MUX on Sensor Inputs