The Self-Biasing Current Generator: A Useful Transconductance Cell

Abstract

This brief presents a bulk-driven transconductance cell using a basic self-biasing current generator circuit. The proposed cell employs two N-type and P-type current mirrors to form a positive feedback structure. The circuit is adaptively biased by diode-connected topologies of the current mirrors. The bulk terminals of the P-type transistors act as the input nodes to employ the proposed circuit as a transconductance cell. Thanks to its symmetrical self-biasing topology, a tailed double-output differential structure is achieved. An additional current source is also used to ensure the stability and adjust the amount of the produced transconductance. The circuit is simulated using a 0.18-µm CMOS technology to verify its operation.