Rail-to-rail class AB CMOS tunable transconductor with -52dB IM3 at 1MHz

A novel CMOS tunable transconductor is presented. The circuit operates in classAB hence featuring power efficiency. The internal feedback employed and the use of a linearized triode transistor for voltage-to-current conversion allows achieving high linearity. Rail-to-rail input range is obtained by using floatinggate transistors. Measurement results for a test chip prototype in a 0.5µm standard CMOS process show an IM3 of -52.13dB at 1MHz for a 2Vpp input and a power consumption of 2.2mW.