A novel Operational Transconductance Amplifier with high Gm using improved differential current redistribution technique (DCRT)

A novel CMOS Operational Transconductance Amplifiers (OTA) featuring with excellent transconductance performance is described in this paper. The OTA utilizes the proposed differential current redistribution technique (DCRT) that adaptively distributes the differential current generated by the input differential voltage to get the high Gm performance. In addition, the linearity of the OTA is enhanced due to the optimized redistribution strategy the modified DCRT adopts. Moreover, good frequency behavior and excellent transient response of the proposed OTA are obtained thanks to the DCRT for the lack of internal nodes. The OTA implemented in a CSMC 0.5μm BCD technology only consumes 5mW. The DC gain of 90dB, unity gain bandwidth (UGB) of 200MHz is achieved and the slew rate is up to 60V/ns.

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