A DESIGN TECHNIQUE FOR A HIGH-GAIN, 10-GHZ CLASS-BANDWIDTH GAAS-MESFET AMPLIFIER IC MODULE

A high-gain wide-band amplifier IC module is needed for high-speed communication systems. However, it is difficult to expand bandwidth and maintain stability. This is because small parasitic influences, such as bonding-wire inductance or the capacitance of the package, become large at high frequencies, thus degrading performance or causing parasitic oscillation. In this paper, a new design procedure is proposed for the high-gain and wide-band IC module, using stability analysis and a unified design methodology for IC's and packages. A multichip structure is developed using stability analysis and the requirements for stable operation are determined for each IC chip, package, and interface condition between them. Furthermore, to reduce the parasitic influences, several improvements in the interface and package design are clarified, such as wide-band matching and LC resonance damping. IC design using effective feedback techniques for enlarging the bandwidth are also presented. The IC's are fabricated using 0.2-mu-m GaAs MESFET IC technology. To verify the validity of these techniques, an equalizer IC module for 10-Gb/s optical communication systems was fabricated achieving a gain of 36 dB and a bandwidth of 9 GHz.