A sensor used to measure physiological characteristics of body tissues is provided. The physiological sensor includes a first light source assembly having a first light source in parallel with a second light source. Each of the first light source and the second light source have an anode and a cathode. A second light source assembly includes a third light source in parallel with a fourth light source. Each of the third light source and the fourth light source have an anode and a cathode. The anode of the first light source is electrically connected to the cathode of the second light source, the anode of said third light source, and the cathode of said fourth light source. The anode of the third light source is electrically connected to the cathode of the fourth light source.