High performance, low-cost chip-on-board (COB) FDDI transmitter and receiver for avionics applications

Abstract

Recent trends in the avionics industry have focused on the use of commercial-off-the-shelf electronic components for specialized system applications. Deviating from the conventional concept of high performance at any cost, the idea of producing avionics optoelectronic modules at a low cost-to-performance ratio (or high performance-to-cost ratio) is emerging. Laminate based/Chip-on-Board multichip module interconnect (MCM-L/COB) technology is a robust and flexible packaging approach which has demonstrated its effectiveness in low-cost consumer electronics for many years, and is rapidly finding acceptance in high performance electronics applications. In this paper, we present our results on the development of ARINC 636 compatible Fiber Distributed Data Interface (FDDI) fiber-optic transmitter and receiver modules using MCM-L/COB packaging technology. These modules are equivalent to the industry standard FDDI modules in footprint, but they are required to function with higher performance and be able to operate under more severe environmental conditions than commercial grade components. Through a careful MCM-L design layout and optical subassembly (OSA) selection process, we have demonstrated COB FDDI transmitter and receiver modules that exhibit excellent results over the temperature range of -40 to 110/spl deg/C. Our test results show that the transmitter minimum average output power is about -13 dBm over the operating temperature range. This is 3 dB better than the standard commercial grade FDDI transmitters. Operating at 125 Mb/s, an overall link margin greater than 22 dB can be achieved by these high performance MCM-L/COB optoelectronic modules.