Systems and methods for low power pulse oximetry

An optical sensor, comprising:

• a light emitter;
• a detector configured to output a signal representative of light from the light emitter received at the detector;
• and
• a control unit configured to:
• illuminate the light emitter according to set current drive parameters, the current drive parameters set based on hardware noise contributing to the signal output by the detector, and further based on ambient noise contributing to the signal, the current drive parameters including a current pulse amplitude and duty cycle of the light emitter;
• and
• adjust the current drive parameters of the light emitter to maintain a target signal to noise ratio of the signal output by the detector.

A method for an optical sensor, comprising:

• characterizing hardware noise of the optical sensor as a function of average detector current;
• illuminating a light emitter of the optical sensor according to set sensor parameters, the sensor parameters set based on the hardware noise characterization and the average detector current of the optical sensor, the sensor parameters including current drive parameters of the light emitter;
• and
• adjusting the current drive parameters of the light emitter to maintain a target signal to noise ratio of the signal output by the optical sensor.