DVCC-based Low-power RF Filter with 32 nm CNFETs

This work presents a wide-band active filter for RF receiver. The design uses Carbon Nanotube-FET (CNFET) based differential voltage current conveyor (DVCC) for the implementation of the proposed filter. The filter is designed to operate Ku-band frequencies (12-18 GHz), which is used in satellite communication. Additionally, CMOS based circuit and CNFET-based circuit for DVCC are compared for the performance evaluation. HSPICE simulations have been carried out to test the design aspects of the circuit. The CNFET-based circuit has better results in terms of 60 % reduction in the power consumption and about six times improvement in the bandwidth. The filter utilizes low supply voltage of 0.9 V and consumes 524 µW only. The proposed filter outperforms the existing CMOS-based designs which suggests its usage for low-power high-frequency analog circuits.

Realization of Linear and Non-linear circuits with Variable Gain DVCC

The analog circuits are two types; linear and non-linear. The analog circuits are, might be, with or without feedback. In general, linear circuits need negative feedback while negative or positive feedback needed in non-linear circuits. Here, the VG-DVCC is proposed for the realization of linear and non-linear circuits. Basically, this VG-DVCC is a low-gain active network block. Thus, feedback is not needed for the realization of linear circuits whereas non-linear circuits needed feedback. This paper highlights the realization of linear circuits: Instrumentation Amplifiers, Active Filters, and nonlinear circuits: Schmitt Trigger comparator, Square wave generator with variable gain differential voltage current conveyor. The performance is validated by simulation using ADS.

A New Method for Increasing Quality Factor in Active Filters

In this paper, we present a new method increasing quality factor of active filter structure in the literature and a new designed filter. The new method is easily applied to all different filter modes with the proper feedback circuit. The center frequency of the filter remains constant as quality factor of filter increases. Also, quality factor can be also tuned electronically by changing the biasing current of the feedback circuit. Furthermore, the performance of the method is demonstrated by CMOS simulation of differential voltage current conveyor and transconductance amplifier. Quality factor value of the filter can also be easily adjusted electronically between 1 and 20 with the presented method. Finally, an application example of the presented method is presented for double tuned amplifier for intermediate frequency pre-amplifier of FM receiver.