Hi Sir / Madam ,
This ia vengad here from Avnet , One of my customer is trying to implement ECG Application based on ADS1294R . customer is doing the testing in proto board ( Respiration mode (internal) set ON ) . Input signal is fed from PS420 (Fluke Simulator). They are getting ECG output from CH2, CH3 and CH4 with some 50Hz noise on baseline . In CH1 (Respiration out), They got output with lot of noise. They are not able to make out clear envelope of Respiration signal. The input components to ADS1294R, used are with values same as given in the data sheet. They have also tried with different setting (Modulating frequency, Channel Gain, Phase) and we could get similar outputs with noise.
Please do find some more input from customer :
- output data from other ch2 to ch4 gives ECG shaped waveforms when plotted.
- Respiration out is there with noise as well as doesn’t represent the input.
- when they have studied the captured data, for particular gain, the MSB byte is maintaining the same value for all samples. The MSB byte changes to another same value for different gain. The MSB byte value doesn’t seem to be proportional with gain. Also as the MSB byte is constant value, does it add any significance in decoding?
Is the respiration data format is different from other channels?
Please arrange to get the decoding format for the Respiration data out and for other channels. - Data captured with 3 different gains are attached for reference. Input signal is – ECG-60BPM, Respiration – 30RPM, Baseline – 1000 Ohms, Delta R – 3 Ohms. The input is fed from Fluke Simulator PS420. Register setting : Modulating frequency – 64KHz, Phase – 135o .
Regards/
vengad