On the <italic>g</italic>_m-Boosted Miller-Effect Minimized Inverter-Cascode Transimpedance Amplifier for Sensor Applications

Abstract

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.

Keywords

• Analog CMOS circuits
• gm-boosting
• inverter-cascode transimpedance amplifier
• small-signal analysis
• simplified inspection-based analysis technique