A High Frequency Large Signal Very Low Distortion Transconductor

A high frequency very low distortion transconductor is introduced. The Total Harmonic Distortion (THD) is lower than -60 dB's for a differential input voltage of 2.4 Vptp (Volts peak to peak), which represents 41 % ofthe transconductor bias current. The dynamic range is in the order of 84 dB's. Furthermore, this structure presents low sensitivity to mismatches. The supply voltages are only +/- 2.5 volts. An Operational Transconductance Amplifier (OTA) and a second order filter, based in the proposed transconductor, have been fabricated in a 3 ¿m N-well process. The OTA transconductance is 150¿A/V and the center frequency of the filter is 1.75 MHz. The quality factor can be adjusted from 1 to 50. The experimental results are in good agreement with the expected and simulated results.

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