Jitney parallel optical interconnect

Abstract

The Jitney Parallel Optical Interconnect consists of a transmitter module, a receiver module, and a cable capable of sending 1 GigaByte/sec over 1-100 meter spans. This technology has been developed to be cost competitive with copper bus technology, while still offering all the features of optical interconnects. Jitney has a two Byte wide interface with extra lines for clocking and flow control, each line supporting 500 Mb/sec. The modules use a standard logic level (LVDS) and power supply (+3.3v), and mount on standard PC cards using standard vapor phase soldering processes. The ribbon cable connector plugs directly to the module. The transmitter module contains a VCSEL array chip with 20 emitters, driven by a 20 channel CMOS driver IC. The receiver module contains a 20 channel GaAs MESFET receiver array OEIC. Each module also contains a 20 channel plastic molded optical coupler to transfer light to and from the chips to the fibers in a fiber array connector. The modules themselves are plastic molded leadframes, with the optical alignment features for the optical coupler and the array connector molded into the module housing. The cable consists of a 20 fiber ribbon of a 200 μm core fiber of either step or graded index of refraction profile. The entire package has assembly tolerances in the ±50μm range, and thus is assembled using passive alignment techniques. Test vehicle driver and receiver chips indicate the necessary speed, sensitivity, and uniformity for optical bus operation.