BW extension in shunt feedback transimpedance amplifiers using negative miller capacitance

The large input capacitance seen at the input of transimpedance amplifiers (TIA) used in optical receivers is usually the primary BW bottleneck. A new approach for increasing the BW of shunt feedback TIA’s utilizing negative miller capacitance is presented which incurs no significant power, area or noise penalty. With this technique, 10 Gb/s performance is made possible with the usage of just a single common emitter stage resulting in a low power and low area design. The differential TIA was implemented in a 0.18 μm SiGe BiCMOS technology and consumes 10.9 mA from a 1.8 V supply. It provides 495 Ω gain, 7.7 GHz BW and has a noise density of 5.8 pA / √Hz @ 1 GHz. The technique is not technology dependent and may be applied to CMOS designs as well.