High efficiency 10 Gb/s optical modulator driver amplifier using a power pHEMT technology

This paper presents the design and performance of a high efficiency GaAs MMIC distributed amplifier for 10 Gb/s optical driver applications. The power consumption is only 550 mW, approximately 40% lower than typical reported results for this application. It is shown that while the commonly-used cascode topology gives higher gain-BW performance, the ordinary common-source design gives better efficiency and stability performance. This makes it a better choice for 10 Gb/s applications when a suitable high power pHEMT process is used.