hello:
Sorry to bother you .
I designed two boards according to TI"s blood oxygen saturation. one board uses transmission type sensor,while another uses reflective sensor. The Schematic diagram and program of the two boards are the same.
Everytime I try to collect waveform by the board which use transmission type sensor, I can collect signal easily. The signal just like :
But when I try to collect waveform by the board which use reflective sensor, sometimes I can get the signal ,but more often than, I can't get the signal. the signal just like: