Realization of Linear High-Frequency Transconductance in CMOS-Technology

It is shown that a CMOS class AB voltage-current converter circuit can be used as a wideband transconductor with variable highly linear transconductance. Linearity error less than 0.1% and THD of 0.16% for output signal current of 200% of the quiescent current value, and bandwidth of 5 MHz were measured on experimental chips. In addition, the circuit generates a useful square-law function.