Osi optoelectronics photodiodes solderable chip planar diffused osi optoelectronics s 25c a photoconductive type solderable chip photodiode with an active area of 258mmsup2 the device represents a simple low cost approach to applications requiring a large active area photodetector for large signal outputs the detectors can be connected directly to a current meter or across a resistor for voltage measurements alternately the output can be measured directly with an oscilloscope or with