A 10 Gb/s CMOS optical receiver using modified regulated cascade scheme

In this work, a 10 Gb/s CMOS optical receiver using the modified regulated cascade scheme is developed based on the TSMC 0.18 mum CMOS technology. The proposed receiver includes a transimpedance amplifier, limiting amplifier, open-drain output buffer and offset cancellation unit. By using the feedback oscillation technique, the overall optical receiver can compensate input capacitances of the photodiode and bonding pad. Our transimpedance amplifier has a bandwidth more than 6.3GHz at a transimpedance gain of 800 Omega and the maximum allowed input capacitance of 300 fF. The limiting amplifier using the feedback oscillation, active inductor peaking, and Cherry-Hooper schemes can pull up the high-frequency band and enlarge the bandwidth. The -3 db cutoff frequency of the proposed limiting amplifier is 6.7 GHz, and the voltage gain is 37 dB at a supply voltage of 1.8 V. The die size of the proposed optical receiver is 1,400 mum times 550 mum. As compared to the conventional work, the proposed optical receiver can have lower hardware cost at a similar receiving performance for 10 GB/s optical data communication