Sensor characterization through forward voltage measurements

A method for measuring oxygen saturation, the method comprising:

• measuring, by circuitry, a first diode voltage at a light emitting diode while applying a first current through the light emitting diode;
• measuring, by the circuitry, a second diode voltage at the light emitting diode while applying a second current through the light emitting diode;
• measuring, by the circuitry, a third diode voltage at the light emitting diode while applying a third current through the light emitting diode;
• determining, by the circuitry, a series resistance for the light emitting diode based on the first diode voltage, the second diode voltage, and the third diode voltage;
• determining, by the circuitry, an intensity of a received photonic signal corresponding to an output photonic signal output using the light emitting diode;
• determining, by the circuitry, an oxygen saturation level based on the intensity of the received photonic signal and the series resistance;
• and
• outputting, by the circuitry, an indication of the oxygen saturation level.

A system for measuring oxygen saturation, the system comprising:

• a sensor device comprising a light emitting diode;
• an oximetry device comprising circuitry configured to:
• measure a first diode voltage at the light emitting diode while applying a first current through the light emitting diode;
• measure a second diode voltage at the light emitting diode while applying a second current through the light emitting diode;
• measure a third diode voltage at the light emitting diode while applying a third current through the light emitting diode;
• determine a series resistance for the light emitting diode based on the first diode voltage, the second diode voltage, and the third diode voltage;
• determine an intensity of a received photonic signal corresponding to an output photonic signal output using the light emitting diode;
• determine an oxygen saturation level based on the intensity of the received photonic signal and the series resistance;
• and
• output an indication of the oxygen saturation level.