Sun Sensor Power Consumption

Subsystem	Sun Sensor
Author	Arnold Young & Sarah Brennan
Original Date	2/23/98
Last Review	2/25/98
Relevant Specs	Light Off: R_sensor = 100k from measurements Light On: R_sensor = 700 Ohm from measurements P_allowed = 250 mW
Specs Source	Jameco
Assumptions Made	The sensor obeys Ohm's Law, V = IR, so that the power is equal to V²/R.
Calculations/Method of Measurement	Light Off: R_sensor = 100k V_sensor = (100k/(100k+1k)) * (5 V) = 5 V => P = 5²/100k = 0.25 mW Light On: R_sensor = 700 Ohm V_sensor = (700/(700+1k)) * (5 V) = 2.06 V => P = 2.06²/700 = 6.1 mW
Results	P = 0.25 mW (light off) P = 6.1 mW (light on)