Design and performance of an optoelectronic matrix switch using Si-p-i-n photodiodes

Switching speed, isolation, optical-source requirements, and attainable matrix dimensions of an optoelectronic matrix switch using Si p-i-n photodiodes are discussed. By charging the internal capacitance of the diode with a photocurrent, forward bias voltages are attained that establish off-states. The novel features of the matrix switch are that the switch elements have high output impedance at off-states, and no electrical power is required to establish the off-states. This leads to advantages in fabricating large-dimension matrix switches