Plotting PPG Waveform

Hello Mohammad,

You may use any of the 2 registers (LED2-ALED2VAL or LED1-ALED1VAL) you mentioned to plot the PPG waveform.

LED2VAL contains the PPG data for LED2 (Red) with ambient signal.

LED1VAL contains the PPG data for LED1 (IR) with ambient signal.

LED2-ALED2VAL contains the PPG data for LED2 (Red) without the ambient signal.

LED1-ALED1VAL contains the PPG data for LED1 (IR) without the ambient signal.

Thanks Praveen.

Also, what would be the methodology for measuring the heart rate using above registers?

Thanks.

I have discussed the methodology to estimate heart rate from the ADC registers in the AFE44xx FAQ post (refer to link below)

http://e2e.ti.com/support/applications/high_reliability/f/30/t/369445.aspx

Thanks, I will try to see if I can implement that.

I have one additional question - Should I be using the LED1VAL and LED2VAL for calculating SPO2 and heart rate, or should I be using the LED2-ALED2VAL and LED1-ALED1VAL?

From the reference TI designs, it looks like LED1VAL and LED2VAL are always used.

Thanks.

Hello Mohammad,

Use the 2 registers LED2-ALED2VAL and LED1-ALED1VAL to calculate the SpO₂ and any one of the 2 registers LED2-ALED2VAL / LED1-ALED1VAL (depending on the strength of the pulsatile signal) to estimate the heart rate.

Regards.