Multi-stream sensor front ends for noninvasive measurement of blood constituents

A conversion processor for a physiological, noninvasive sensor, said board comprising:

• a multi-stream input configured to receive signals from a plurality of detectors in the sensor, wherein the signals are responsive to optical radiation from a tissue site;
• a modulator that converts the multi-stream input into a digital bit-stream;
• and
• a signal processor that produces an output signal from the digital bit-stream.

A front-end interface for a noninvasive, physiological sensor, said front-end interface comprising:

• a set of inputs configured to receive signals from a plurality of detectors in the sensor;
• a set of respective transimpedance amplifiers for each detector configured to convert the signals from the plurality of detectors into an output signal having a stream for each of the plurality of detectors;
• and
• an output configured to provide the output signal.