Hi Trapp, Few suggestions to get better signal on the wrist using SFH7072. 1) Are you using Green LEDs to get heart rate signal? If yes, please make sure to use IR-Cut photodiode (Pin 3 and Pin 10 of SFH7072) as the other photodiode attenuates the Green light. 2) You can increase the LED current even higher to get the better signal. Please note that this can lead to ADC saturation and which can be mitigated by using the Offet cancellation DAC in the LED phase. 3) Lastly you can increase the TIA gain ( after DC has been removed ) to amplify the signal. 4) Avoid noise pick up from the AC mains by running the measurements from battery operated instruments (i.e. Laptop) Regards, Prabin.
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