Hello! I'm trying to design EMG electrodes using the LMP7704 and I have the schematic (attached) breadboarded. It is using a DRL as well. As you can see E1 and E2 are the electrode inputs and I'm using Eout to view the signals on a oscilloscope but eventually it will go to a MCU. So, when Eout is connected to a scope I would expect to see some kind of muscle contractions in the form of high frequency oscillations; however, it seems like the inputs are not sensitive enough to detect them. Vcc = 2.5 and Vdd = -2.5. The circuit seems like it should work but I'm inexperienced in biopotential acquisition so maybe I'm missing something. As you can see there is no filtering, rectification, etc. of the signal, yet. I want to see the raw EMG signal first if possible. Any insights are much appreciated, thanks in advance!
141.9 KB Views: 8