Hello, I wrote earlier, that we develop the device for the medical industry. It will look like a smartwatch.
The main function is to measure the EKG and PPG signals of the user and send the data to the doctor.
For this purpose, in our electronic design, we use AFE4950, optical module SFH7072, and nRF9160 MCU as a host and other components.
In parallel with the electronic design, we did the FW development. So the firmware driver of the AFE4950 was done
and successfully tested on the dev board AFE4950EVM. We got the PPG signals and they looked good.
Recently we got our designed board ready to test with FW.
We flashed our board with the FW which includes the tested firmware driver of the AFE4950.
Made a lot of measurements and the PPG signals didn't look good.
Could TI support us to get a good quality PPG signal on our designed board?
More details from today's testing:
"We have the following situation with PPG measurement by the AFE4950 chip. A map of registers in MIX mode is loaded into it. We measure ECG at 500Hz and PPG at 50Hz. ECG measurements look reliable, but PPG is just some fluctuations. At the same time, the nature of these fluctuations changes if you touch the ECG electrodes. So, there is an influence of the ECG channel on the PPG measurement."
Also, right now, we have seen the influence of PPG on ECG too on our device.
(It is the same as a map of registers in MIX mode).
When one person touches ECG electrodes but another person brings some object to the PPG sensor we can see that the ECG graph changes.
(It is the same as a map of registers in MIX mode).
When one person touches ECG electrodes but another person brings some object to the PPG sensor we can see that the ECG graph changes.
