Gigabit CMOS current-mode optical receivers for high-speed digital interface applications

This paper introduces a number of current-mode input configurations for gigabit CMOS optical receivers, including common-gate, regulated-cascode (RGC), current-mirror, etc. Unlike conventional voltage-mode input configurations, the current-mode designs effectively isolate the large input parasitic capacitance from the determination of the bandwidth, hence achieving wide bandwidth for comparable transimpedance gain and power consumption characteristics. Here, noise issues are less stringent since the target applications of these optical receivers include short-reach high-speed digital interface for multimedia consumer electronics, and possibly the emerging gigabit interface for storage networks.