Hello,
I'm working in a device where we need a EEG device with a single ECG channel and respiration circuit. I already have a EEG device without the ECG and I started designing the second device using the ADS1299 for the EEG and a discrete channel of ECG using a INA129 and a passband filter. The output of the filter was sampled by a MCU's ADC.
Then, yesterday I discovered what I think might be a better solution that is to use a ADS1292R which gives me more ECG signals and also has the respiration circuitry for less money and less space that my previous solution.
Regarding this setup I have a couple of questions.
First, Could I supply the ADS1292R with the same +-2.5V (AVDD) supply I'm using for the ADS1299? The datasheet specifies that it can work with up to 5.25V fo AVDD so I guess there would be no problem there but in that case, will the internal reference have the same values specifies in the datasheet?
Second, Since I will hace a bias voltage already connected to the body that is provided by the ADS1299, would it cause any problem if I connect the BIASINV of the ADS1299 and the RLDINV ADS1292R as shown in figure 53 of page 56 of the ADS1292R datasheet? Theoretically both the BIAS and the RLD are the same thing but called different in both devices I think.
Am I correct or am I missing something?
Thank you.