A transconductance enhancement technique for bulk-driven OTAs working in weak inversion

A proposed transconductance enhancement technique for bulkdriven OTAs working in weak inversion is presented in this paper. The basic idea is to use a bulk-driven input differential pair employing the auxiliary amplifier and positive feedback technique to enhance transconductance, which improves the enhancement ratio of transconductance from (n + 1)/ (n − 1) to (n + 2)/(n − 1). The proposed amplifier based on the mentioned technique is simulated on UMC 180 nm process with the help of Spectre. The simulation results demonstrate that the transconductance of the bulk-driven OTAs working in weak inversion improves almost 50% with just a little increased power consumption compared to the conventional counterparts.

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