Current-Mode Universal Biquad Using Current Followers : A Minimal Realization

A new universal biquad filter is presented which employs a minimum number of active elements (only three current followers (CF)) along with a minimum number of passive components (i.e. only two resistors and two capacitors). The new circuit provides all the five standard filter responses (namely lowpass, bandpass, highpass, notch and allpass) from the same structure without requiring any component matching conditions and with explicit current outputs available from high output impedance terminals. The workability of the proposed universal biquad, realized with unity-gain current followers implemented in 0.35 μm CMOS and operated from 1.65 volts DC power supplies, is established by SPICE simulations.

[1]  E. Tlelo-Cuautle,et al.  Synthesis of VFs and CFs by Manipulation of Generic Cells , 2006 .

[2]  Shahram Minaei,et al.  A 22.5 MHz current-mode KHN-biquad using differential voltage current conveyor and grounded passive elements , 2005 .

[3]  Roman Sotner,et al.  Influence of mirroring of current output responses through grounded passive elements , 2010, 20th International Conference Radioelektronika 2010.

[4]  S. S. Gupta,et al.  Universal Voltage-Mode/Current-Mode Biquad Filter Realised with Current Feedback Op-Amps , 1997 .

[5]  Roman Sotner,et al.  Current-Controlled Current-Mode Universal Biquad Employing Multi-Output Transconductors , 2009 .

[6]  Santiago Celma,et al.  Universal filter using unity-gain cells , 1995 .

[7]  Montree Siripruchyanun,et al.  Electronically Controllable Current-Mode Universal Biquad Filter Using Single DO-CCCDTA , 2008 .

[8]  Hussain A. Alzaher.  A CMOS Digitally Programmable Universal Current-Mode Filter , 2008, IEEE Transactions on Circuits and Systems II: Express Briefs.

[9]  Raj Senani,et al.  New universal filter using only current followers as active elements , 2006 .

[10]  George Souliotis,et al.  Current-mode filters based on current mirror arrays , 2008 .

[11]  D. Biolek,et al.  Active Elements for Analog Signal Processing: Classification, Review, and New Proposals , 2008 .

[12]  Shen-Iuan Liu,et al.  New current mode biquad filters using current followers , 1995 .

[13]  H. A. Alzaher,et al.  Current-mode universal filter using unity gain cells , 1999 .

[14]  Roman Šotner,et al.  Universal Tunable Current-Mode Biquad Employing Distributed Feedback Structure with MO-CCCII , 2010 .

[15]  S. S. Gupta,et al.  New voltage-model/current-mode universal biquad filter using unity-gain cells , 2006 .

[16]  Muhammad Taher Abuelma'atti,et al.  Current-mode universal filters using unity-gain cells , 1996 .

[17]  Jan Jerabek,et al.  Fully-differential current amplifier and its application to universal and adjustable filter , 2010, 2010 International Conference on Applied Electronics.