Masaki Hirose

An ultracompact, 2-cc-size, 0.64-W 2.5-Gbit/s optical receiver module combined with an MU receptacle

Summary form only given. Recently, optical communication systems have been applied to various field such as local area networks (LANs), optical interconnections, SDH/SONET, and wavelength-division multiplexing (WDM) systems. To achieve these systems cost-effectively, some trials have been made to realize low-power and small-size optical modules. We have developed an ultra-compact and low-power 2.5-Gbit/s optical receiver (OR) module based on a novel structure and advanced IC design. For drastic size reduction, we used the following design schemes: (1) a butterfly package merged with an MU receptacle (MU-R), (2) multichip module (MCM) technology for assembling ICs, and (3) advanced IC design to eliminate external components that obstruct size reduction.

An ultracompact, 2-cc-size, low-power 2.5-Gb/s optical receiver module incorporating an MU receptacle

This paper describes an ultracompact, -3-V-supply, 2.5-Gb/s optical receiver module. For miniaturization of a gigabit-class receiver module, we used multichip configuration and bump technology, and we incorporated a miniature unit-coupling (MU) receptacle for small-size optical interface. To eliminate required external adjustment devices in the module for reduction of module size and assembling cost, we introduced new circuit techniques; the multistage automatic offset canceling technique is used for the postamplifier, and the sample-and-hold phase-locked loop (PLL) technique is employed for the clock and data recovery circuits. All the ICs were designed to operate at a low DC power supply of -3 V. The IC current was reduced by using 0.5-/spl mu/m Si bipolar process technology. The volume is only 2 cc (9/spl times/30.3/spl times/ 7.7 mm/sup 3/), including the MU receptacle. The experimental results show that the receiver has a wide dynamic range, from more than -2 to -19.4 dBm in optical input. These results were obtained without making any external adjustments. The module consumes a total power of 0.64 W.

A compact MU-interface, 2.5-Gb/s optical transmitter module with LD-driver IC embedded in L-shaped wiring substrate

A 6.2-cc MU interface optical transmitter module has been developed in a compact packaging configuration that allows modules to be mounted side by side on a system board. The module employs an MU receptacle for optical output and miniature coaxial receptacles for electrical input. An L-shaped high-speed wiring substrate in a package cavity allows thermal isolation of a laser-diode driver IC (LD-DR) from the 1.55-/spl mu/m distributed feedback laser diode (DFB-LD) mounted on a thermoelectric (TE) cooler. A confocal two-aspheric-lens circuit is used for high-performance coupling of the DFB-LD to a dispersion-shifted fiber (DSF). A module using the proposed configuration has been evaluated at temperatures from 10-65/spl deg/C. Experiments with the module showed good electrical performance at a bit rate of 2.5 Gb/s, low power dissipation (less than 1.8 W; only 0.33 W for the LD-DR), and high optical coupling efficiency (over 50%).