Composite Transistor Cell Using Dynamic Body Bias for High Gain and Low-Voltage Applications

Abstract

In this work, a new composite transistor cell using dynamic body bias technique is proposed. This cell is based on self cascode topology. The key attractive feature of the proposed cell is that body effect is utilized to realize asymmetric threshold voltage self cascode structure. The proposed cell has nearly four times higher output impedance than its conventional version. Dynamic body bias technique increases the intrinsic gain of the proposed cell by 11.17 dB. Analytical formulation for output impedance and intrinsic gain parameters of the proposed cell has been derived using small signal analysis. The proposed cell can operate at low power supply voltage of 1 V and consumes merely 43.1 nW. PSpice simulation results using 180 nm CMOS technology from Taiwan Semiconductor Manufacturing Company (TSMC) are included to prove the unique results. The proposed cell could constitute an efficient analog Very Large Scale Integration (VLSI) cell library in the design of high gain analog integrated circuits and is particularly interesting for biomedical and instrumentation applications requiring low-voltage low-power operation capability where the processing signal frequency is very low.

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“…Moreover, improved composite transistors with forward-body-bias offer additional features to increase the voltage gain [22].…”

DTMOS Transistor with Self-Cascode Subcircuit for Achieving High Bandwidth in Analog Applications

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A Novel Technique to Achieve High Bandwidth at Low Supply Voltage

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“…ĭ F is the surface potential at threshold (typically | í 2ij F | equals 0.6 V). V SB is the sourceto-body voltage [6].…”