In this paper two new voltage-mode (VM) universal filters employing three plus-type differential voltage current conveyors (DVCC+s) and grounded passive elements are presented. The first proposed filter is a single-input five-output (SIFO) circuit which can realize simultaneously all of the standard responses, i.e. low-pass (LP), band-pass (BP), high-pass (HP), all-pass (AP) and notch (NH) from the same configuration. The second proposed circuit is a three-input single-output (TISO) universal filter for realizing standard responses depending on the selection of the input signal from the same topology. Both of the proposed filters have the advantage of a high input impedance, which enables easy cascading to obtain higher order filters. The proposed filters are simulated using the SPICE program to verify the theoretical analysis.

All-Grounded Passive Elements Voltage-Mode DVCC-Based Universal Filters

This paper presents design of an active building block for analog signal processing, named as current-controlled differential difference current conveyor (CCDDCC). Its parasitic resistances at X-terminal can be controlled by an input bias current. The proposed element is realized in a CMOS technology. It displays usability of the new active element, where the maximum bandwidth of voltage and current followers are around 1 GHz, 100 MHz, respectively. The THD is obtained around 0.8% within 0.6 Vp–p input range. The power dissipation of a CCDDCC at 10 μ A biased current is obtained around 1.35 mW with ± 1.25 V power supplies. In addition, grounded capacitor-based floating capacitance multiplier and current-mode (CM) multiple-input single output (MISO) second-order universal analog filters are included as the applications. For realization of a grounded capacitor-based floating capacitance multiplier, it employs three CCDDCCs and one grounded capacitor without resistor connections. The capacitance can be tuned electronically through the bias current. The filter offers the simultaneous realization five type standard filter responses. The quality factor and the frequency response parameters can be independently tuned. The non-ideal effects of the developed structures are examined. SPICE simulation results of proposed CCDDCC and its applications are also presented.

CMOS-based current-controlled DDCC and its applications to capacitance multiplier and universal filter

http://www.te.kmutnb.ac.th/~msn/resistorlessmicro.pdf

Resistorless dual-mode quadrature sinusoidal oscillator using a single active building block

This paper describes a current-mode third-order quadrature oscillator based on current differencing transconductance amplifiers (CDTAs). Outputs of two current-mode sinusoids with phase difference are available in the quadrature oscillator circuit. The oscillation condition and oscillation frequency are orthogonal controllable. The proposed circuit employs only grounded capacitors and is ideal for integration. Simulation results are included to confirm the theoretical analysis.

https://downloads.hindawi.com/journals/apec/2009/789171.pdf

Current-Mode Third-Order Quadrature Oscillator Using CDTAs

A current/voltage-mode third-order quadrature oscillator based on current differencing transconductance amplifiers (CDTAs) is presented in this paper. Outputs of two current-mode and two voltage-mode sinusoids each with 90 phase difference are available in the quadrature oscillator circuit. The oscillation condition and oscillation frequency are independently controllable. The proposed circuit employs only grounded capacitors and is ideal for integration. Simulation results are included to confirm the theoretical analysis.

Electronically tunable third-order quadrature oscillator using CDTAs

Two current-mode and/or voltage-mode quadrature oscillator circuits each using one fully-differential secondgeneration current conveyor (FDCCII), two grounded capacitors, and two (or three) grounded resistors are presented. In the proposed circuits, the current-mode quadrature signals have the advantage of high-output impedance. The oscillation conditions and oscillation frequencies are orthogonally (or independently) controllable. The current-mode and voltage-mode quadrature signals can be simultaneously obtained from the second proposed circuit. The use of only grounded capacitors and resistors makes the proposed circuits ideal for integrated circuit implementation. Simulation results are also included.

Quadrature Oscillators with Grounded Capacitors and Resistors Using FDCCIIs

A new high input impedance voltage-mode universal biquadratic filter with one input terminal and five output terminals is presented. The proposed circuit uses three differential voltage current conveyors (DVCCs), four resistors, and two grounded capacitors. The proposed circuit can realize all the standard filter functions—lowpass, bandpass, highpass, notch, and allpass—simultaneously, without changing the passive elements. The proposed circuit enjoys the features of high input impedance, orthogonal control of resonance angular frequency and quality factor, use of only grounded capacitors, and low active and passive sensitivities.

High Input Impedance Voltage-Mode Universal Biquadratic Filter with One Input and Five Outputs Using Current Conveyors

A new quadrature oscillator circuit using three multiple outputs second-generation current conveyors (CCIIs), two grounded capacitors and three resistors are presented. Two high output impedance current-mode signals and two voltage-mode signals each pair with 90/spl deg/ phase difference are available in the proposed circuit. The oscillation condition and oscillation frequency are independently controllable through grounded resistors. The use of only grounded capacitors makes the proposed circuit ideal for integrated circuit implementation. Experimental results are also included.

Hung-Pin Chou

Papers

Quadrature Oscillators with Grounded Capacitors and Resistors Using FDCCIIs

High Input Impedance Voltage-Mode Universal Biquadratic Filter with One Input and Five Outputs Using Current Conveyors

Current-mode and voltage-mode quadrature oscillator employing multiple outputs CCIIs and grounded capacitors