A monolithically integrated 1 x 4 switchable photodiode array with preamplifier for programmable frequency filters and optical interconnects

An InGaAs-InP 1×4 p-i-n photodiode array has been monolithically integrated with switching junction field-effect transistors and a transimpedance preamplifier. The switching on-off ratio at the output of the preamplifier is 60 dB. As an optical receiver, the circuit has a 3-dB bandwidth of 1.1 GHz and a sensitivity of -25 dBm at 1 Gb/s, BER=10/sup -9/, and 1.55-μm wavelength. A programmable frequency filter has been demonstrated as an application of this novel circuit.