A novel multi-input floating-gate MOS four-quadrant analog multiplier

A novel four-quadrant analog multiplier using multi-input floating-gate MOS (MFMOS) transistors has been designed and fabricated using a 2-μm double-poly double-metal P-well CMOS process. It is essentially based on the quarter-square technique which relies on the square-law characteristic of the MOS transistor in the saturation region. The multiplier is realized with only four MFMOS transistors and a current source. The input range is 100% of the supply voltage and accepts either differential, single-ended, or floating input signals. Measured nonlinearity and total harmonic distortion are 0.2% and 0.5%, respectively, under full scale input conditions. Input noise is 170 μV (rms), giving a 95 dB input dynamic range. The power dissipation is 1.1 mW and bandwidth is 12 MHz. Second-order effects on the multiplier performance have also been analyzed