A STUDY TO IMPROVE SYMMETRICAL CMOS OTA BEHAVIOUR IN SUBTHRESHOLD REGION

The current transfer characteristic of the CMOS symmetrical OTA, operating in the subthreshold region, depends much more on channel length modulation then operating in the strong inversion region. In this paper a new method is proposed to reduce the dependence on channel length modulation and to improve the OTA behaviour by changing one of the MOS transistor dimensions in the CMOS symmetrical OTA. The result is proven by SPICE simulations and by measurements.