Patent ID: 8586912

Claim:
A current source for producing an output current that simulates a current generated by an optical patient sensor, the optical patient sensor including a sensor light source having a first characteristic profile and a sensor photodetector having a second characteristic profile, the current source comprising: a light source configured to emit light in response to a drive signal, the light source having a characteristic profile that is similar to the first characteristic profile as to indicate interchangeability between the light source and the sensor light source; a first photodetector configured to produce the output current in response to receiving light from the light source, the first photodetector having a characteristic profile similar to the second characteristic profile as to indicate interchangeability between the sensor photodetector and the first photodetector; and a control unit configured to: receive a signal indicative of light emitted by the light source based on an output of a second photodetector; provide the drive signal to the light source based at least in part on the received signal indicative of light emitted by the light source and a waveform control signal.