Hello
I'm working on a project where I need to capture raw sEMG signals to predict the movement. I've attached my current schematic, it's single supply 5V.
The signal comes from the electrodes and goes into the instrumentation amplifier. I've AC-coupled the inputs with a HPF at 5Hz, I found that part of the circuit in a paper. I'll set the gain of the in amp at +- 60dB and the reference voltage at Vmid. After that it goes through a HPF (@10Hz), a LPF (@500Hz), an inverting opamp (gain = ?, I'll try to match it with the 0-5V input range of the analog input of an arduino board) and at last a LPF (@500Hz).
I have 2 questions that I'm unsure of.
1. I need to bias the inputs of the in amp at Vmid so that the signal is in the operating range of the in amp. Do I do that at the inputs itself or split the Rg resistor and add the bias voltage there. I've seen both.
2. Where do I connect the Vref electrode? After or before the buffer IC3A or split Rg resistor and add there.
For the rest, I think my schematic will work. Other comments are appreciated.
Thanks
I'm working on a project where I need to capture raw sEMG signals to predict the movement. I've attached my current schematic, it's single supply 5V.
The signal comes from the electrodes and goes into the instrumentation amplifier. I've AC-coupled the inputs with a HPF at 5Hz, I found that part of the circuit in a paper. I'll set the gain of the in amp at +- 60dB and the reference voltage at Vmid. After that it goes through a HPF (@10Hz), a LPF (@500Hz), an inverting opamp (gain = ?, I'll try to match it with the 0-5V input range of the analog input of an arduino board) and at last a LPF (@500Hz).
I have 2 questions that I'm unsure of.
1. I need to bias the inputs of the in amp at Vmid so that the signal is in the operating range of the in amp. Do I do that at the inputs itself or split the Rg resistor and add the bias voltage there. I've seen both.
2. Where do I connect the Vref electrode? After or before the buffer IC3A or split Rg resistor and add there.
For the rest, I think my schematic will work. Other comments are appreciated.
Thanks
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