论文信息 - A Very Linear OTA with V-I Conversion based on Quasi-Floating MOS Resistor

A Very Linear OTA with V-I Conversion based on Quasi-Floating MOS Resistor

This paper proposes a novel very linear tunable transconductor based on local feedback loops. The linear V-I conversion is accomplished using MOS resistors based on quasi-floating gate transistors. The absence of current mirrors in the signal path provides low sensitivity to transistor mismatch and decrease of nonlinear distortion. The OTA was designed in a 0.5 mum CMOS technology with plusmn1.65-V supply voltage. Simulation results show a THD of -80 dB at 100 kHz with 1 Vpp input signal. Good linearity of the OTA over a large tuning range is obtained.

[1] Ramón González Carvajal,et al. Biasing CMOS amplifiers using MOS transistors in subthreshold region , 2004, IEICE Electron. Express.

[2] Y. Tsividis. Operation and modeling of the MOS transistor , 1987 .

[3] Hiroshi Yamazaki,et al. An accurate center frequency tuning scheme for 450-KHz CMOS G/sub m/-C bandpass filters , 1999 .

[4] Ko-chi Kuo,et al. A linear MOS transconductor using source degeneration and adaptive biasing , 2001 .

[5] A.J. Lopez-Martin,et al. Very low-voltage analog signal processing based on quasi-floating gate transistors , 2004, IEEE Journal of Solid-State Circuits.

[6] M. Tarsia,et al. Design considerations and implementation of a programmable high-frequency continuous-time filter and variable-gain amplifier in submicrometer CMOS , 1999, IEEE J. Solid State Circuits.

[7] Ramón González Carvajal,et al. The flipped voltage follower: a useful cell for low-voltage low-power circuit design , 2005, IEEE Transactions on Circuits and Systems I: Regular Papers.

[8] Terri S. Fiez,et al. A CMOS transconductor with 80-dB SFDR up to 10 MHz , 2002 .

[9] Edgar Sanchez-Sinencio,et al. CMOS transconductance amplifiers, architectures and active filters: a tutorial , 2000 .