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Need help with configuring AD5940

Thread Summary

The user was using the AD5940 BIA example to measure impedance with a 4-wire setup. They replaced capacitors with 0 Ohm resistors and got incorrect results. The solution involved reconfiguring the switch matrix settings: SWN_AIN1 to SWN_SE0, SWT_AIN1 to SWT_SE0LOAD, ADCMUXP_AIN3 to ADCMUXP_VRE0, and ADCMUXN_AIN2 to ADCMUXN_N_NODE. The user also encountered a frequency mismatch issue, which was resolved by restoring missing initialization lines in the code. The waveform now matches the set frequency and is stable.
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Hello,

I'm using the AD5940 to measure impedances in a test circuit for now, i eventually want to use a 4 wire measurement so i can accurately measure this impedance. I'm using the BIA example on github since the Impedance example did not work for me. (https://github.com/analogdevicesinc/ad5940-examples/tree/master/examples/AD5940_BIA)

Right now my schematic looks like this and I've replaced the capacitors with 0 Ohm resistors. I get data but since I've not set up the matrix correctly I get wrong results (see image below). Can anyone help me to reconfigure the BIA example so it works for me?

Thanks

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