Versatile Tunable Voltage-Mode Biquadratic Filter and Its Application in Quadrature Oscillator

Round 1

Reviewer 1 Report

Well written paper. I would like to see a demonstration of the electronic tunability.

Author Response

Please kindly find the attached file.

Author Response File: Author Response.doc

Reviewer 2 Report

The paper presents a tunable biquadratic filter and its applications in quadrature oscillator. According to the reviewer’s opinion, the paper is well-structured and clear. The topic is interesting and falls within the aim of the journal. In addition, the results are well-presented and could be helpful to further develop the same topic. Therefore, the paper can be accepted for publication in the current form.

Author Response

Please kindly find the attached file.

Author Response File: Author Response.doc

Reviewer 3 Report

The paper is well written and includes simulated and experimental results. However, I have the following concerns and comments:

-          For which specific sensor applications we need such a universal filter that use high voltage supply and consume high power?.  

-          I think that the authors should present a specific sensor application for their circuit.

-          The simulated THD and the 3^rd IMD are very high for very limited input signal (see figs 9 and 10). 4% THD for 120mV and 3.5% 3rd IMD  for 70mV while the voltage supply is +-15V.

-          The measured 3^rd IMD (Fig. 18) show even worst value only -34.54dB for 30mVp.

-          What is the value of dynamic range of the filter? I think it will be quite limited. This should be added and compared to other designs.

-          What is the value of the power consumption of the filter? This should be added and compared to other designs.

Author Response

Please kindly find the attached file.

Author Response File: Author Response.doc

Round 2

Reviewer 3 Report

The paper can be accepted now.