AD8232 gives me no output

Sensors Biometrics
1

Hello,

playing around with an AD8232 module and trying to get a ECG-signal out.

AD8232 is connected to a battery (2xAA cells) and having a oscilloscope on the OUT-signal.

Instead of a ECG I receive a very clean 1.5V signal on OUT.

When disconnecting RA, the signal drops to 0V, while LOD- gives 3V (electrode off)

When disconnecting LA, the signal jumps to 3V, while LOD+ gives 3V

When disconnecting RL (driven electrode), signal drops to 0V, while LOD- and LOD+ are going to 3V

First I had some 50Hz noice, but using now electrodes from my physician the signal is very clean. (Not more than 0,1mV in 200ms/division)

No matter, where I stick the electrodes, i get either 0V, 1,5V oder 3V, but no ECG-signal.

What I am doing wrong?

2

Thanks for reaching out to us on this.

The datasheet https://cdn.sparkfun.com/datasheets/Sen … AD8232.pdf page 6 mentions DC/AC leads-off modes; please verify this is set correctly for your set-up. Also verify the electrodes are attached to the body before powering on, as the voltage filters adjust based on initial values. Finally, try swapping the electrodes for the basic ones included in the kit and verify the electrodes aren’t filtering something out.

It might also be useful to try hooking the set-up into an arduino and following the hook-up guide https://learn.sparkfun.com/tutorials/ad … 1615791300 , so that you might eliminate some variables.

Hope this helps, and happy sparking!