1 V Tunable High-Quality Universal Filter Using Multiple-Input Operational Transconductance Amplifiers

Abstract

This paper presents a new multiple-input single-output voltage-mode universal filter employing four multiple-input operational transconductance amplifiers (MI-OTAs) and three grounded capacitors suitable for low-voltage low-frequency applications. The quality factor (Q) of the filter functions can be tuned by both the capacitance ratio and the transconductance ratio. The multiple inputs of the OTA are realized using the bulk-driven multiple-input MOS transistor technique. The MI-OTA-based filter can also offer many filtering functions without additional circuitry requirements, such as an inverting amplifier to generate an inverted input signal. The proposed filter can simultaneously realize low-pass, high-pass, band-pass, band-stop, and all-pass responses, covering both non-inverting and inverting transfer functions in a single topology. The natural frequency and the quality factors of all the filtering functions can be controlled independently. The natural frequency can also be electronically controlled by tuning the transconductances of the OTAs. The proposed filter uses a 1 V supply voltage, consumes 120 μW of power for a 5 μA setting current, offers 40 dB of dynamic range and has a third intermodulation distortion of −43.6 dB. The performances of the proposed circuit were simulated using a 0.18 μm TSMC CMOS process in the Cadence Virtuoso System Design Platform to confirm the performance of the topology.

Design Optimization of CMOS Folded Cascode OTA Using Water Cycle Algorithm for Enhanced Performance

“…Figures 4 to 8 demonstrate that the voltage gain achieved with the WCA is 98.63 dB, representing a 24.4% increase compared to the previous value of 79.29 dB without utilizing the WCA. In the study [8], the voltage gain is reported as 56.11 dB, while in the study [22], it is stated as 53.9 dB. Additionally, the Gain Bandwidth (GB) is significantly improved with the WCA, reaching 300.5 MHz, which is improve the previous value of 47.8 MHz.…”

“…The power dissipation of the optimized design is reduced by 15.5%, decreasing from 255.6 μW to 216 μW after applying the WCA. In the study [8], the power dissipation is reported as 6.106 μW, while in the study [22], it is noted as 1100 μW and in the study [23], it is state as 540 μW. Moreover, other parameters such as CMRR and settling time (ts) also exhibit improvements through the use of the Water Cycle Algorithm, For temperature influence, this design is room temperatures and note the results are among the acceptable Ring compared to other research as in Table 4.…”

“…The focus of the design appears to be on a foldedcascode CMOS Operational Transconductance Amplifier (OTA) targeted for high-frequency applications. These highfrequency applications may include Analog-to-Digital Converters (ADCs), Digital-to-Analog Converters (DACs), universal filters, and other circuits that operate at elevated frequencies [22]. In order to utilize the WCA for optimization in MATLAB, it is necessary to incorporate the parameters to be optimized into the fitness equation, as depicted in Eq.…”