Large swing, high linearity transconductor in 0.5 μm CMOS technology

The authors investigate the realisation of a low voltage, large swing tunable transconductor in a 0.5 μm CMOS technology which preserves a constant input window for all tuning conditions. To preserve the DR at low voltages, large swings are required. This conflicts with the voltage limitation imposed by the power supply and distortion figures. This structure overcomes the problems related to non-idealities of the modern MOS transistor in terms of tunability range and linearity. The transconductance can be digitally tuned, in 10 coarse steps, and continuously tuned between coarse steps in the range 30-85 μA/V. The large swing properly yields a large dynamic range over power ratio