Search

This paper presents the small-signal operation of a $g_{\mathrm {m}}$ -boosted inverter-cascode transimpedance amplifier which has not been reported previously and whose comprehensive analysis is not available in any reported article or text-book. A simplified sequential equivalent-circuit method is employed which eliminates the need for complicated circuit analysis techniques. The analysis shows that the gain and the gain-bandwidth of the $g_{\mathrm {m}}$ -boosted inverter-cascode transimpedance-amplifier is enhanced by the gain of the $g_{\mathrm {m}}$ -boosting amplifier. This is due to the increased output impedance of the TIA, and, the reduced input-referred miller-effect capacitance through miller-effect trade-off employing the $g_{\mathrm {m}}$ -boosting loop. To verify the actual performance improvement achieved, circuit simulation results as well as measured experimental results are also provided.

A state-of-the-art Monte Carlo simulator is applied to the investigation of the radio-frequency performance of bulk and ultrathin-body single-gate SOI MOSFETs that are designed according to the prescriptions of the 2005 ITRS for analog and mixed-signal applications. We provide an analysis of the signal-delay buildup along the channel and an investigation of the scaling properties of the parameters of the ac equivalent circuit, the transition frequency, and the 3-dB bandwidth of the voltage gain in common-source configuration. A comparison with a standard drift-diffusion approach is presented in order to discuss the main differences between the two transport models in terms of high-frequency ac analysis.