Low-Voltage Tunable Pseudo-Differential Transconductor with High Linearity

ETRI Journal

关键词: low-power and low-voltage circuit;    operational transconductance amplifier (OTA);    linear resistor;    Analog CMOS circuit;   

Others  :  1185770
DOI  :  10.4218/etrij.09.0109.0113

【 摘 要 】

A novel tunable transconductor is presented. Input transistors operate in the triode region to achieve programmable voltage-to-current conversion. These transistors are kept in the triode region by a novel negative feedback loop which features simplicity, low voltage requirements, and high output resistance. A linearity analysis is carried out which demonstrates how the proposed transconductance tuning scheme leads to high linearity in a wide transconductance range. Measurement results for a 0.5 μm CMOS implementation of the transconductor show a transconductance tuning range of more than a decade (15 μA/V to 165 μA/V) and a total harmonic distortion of -67 dB at 1 MHz for an input of 1 V_pp and a supply voltage of 1.8 V.

   

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