16x16 crosspoint switch module with 3.125-Gbit/port optical I/O interfaces based on OIP (optical-interconnection as IP) design concept

An optical interface is expected to solve the problems the electrical counterpart has. However, the conventional optical interface system using optical transceiver modules separately located from LSI packages on a printed circuit board (PCB), electrical interfaces among optical transceivers and LSI packages would limit interconnection speed. In addition, the electrical interface consumes a lot of power to drive the I/O buffers and signal lines on the PCB. To solve these problems, we have proposed a packaging technology to which OIP (Optical-interconnection as Intellectual Property) concept is applied. We developed a 3.125-Gbit/s/port crosspoint switch with 16 optical I/O ports on a 35x35-mm BGA package. It incorporates four small optical I/O modules called PETIT (Photonic/Electronic Tied InTerface).The PETIT consists of a 4-channel VCSEL array, a 4-channel pin-PD array, and a GaAs trans-impedance amplifier on an 8x8-mm ceramic substrate, and a newly developed optical connector interface is attached on the substrate. The sensitivity is 11.9 dBm under 12.5-Gbit/s full-duplex operation of the PETIT.