Abstract: This article presents a resistorless current-mode firstorder allpass filter based on second generation current controlled current conveyors (CCCIIs). The features of the circuit are that: the pole frequency can be electronically controlled via the input bias current: the circuit description is very simple, consisting of 2 CCCIIs and single grounded capacitor, without any external resistors and component matching requirements. Consequently, the proposed circuit is very appropriate to further develop into an integrated circuit. Low input and high output impedances of the proposed configuration enable the circuit to be cascaded in current-mode without additional current buffers. The PSpice simulation results are depicted. The given results agree well with the theoretical anticipation. The application example as a current-mode quadrature oscillator is included.
Abstract: The realization of current-mode quadrature oscillators
using current controlled current conveyor transconductance
amplifiers (CCCCTAs) and grounded capacitors is presented. The
proposed oscillators can provide 2 sinusoidal output currents with 90º
phase difference. It is enabled non-interactive dual-current control for
both the condition of oscillation and the frequency of oscillation.
High output impedances of the configurations enable the circuit to be
cascaded without additional current buffers. The use of only
grounded capacitors is ideal for integration. The circuit performances
are depicted through PSpice simulations, they show good agreement
to theoretical anticipation.
Abstract: This article presents a current-mode quadrature
oscillator using differential different current conveyor (DDCC) and
voltage differencing transconductance amplifier (VDTA) as active
elements. The proposed circuit is realized fro m a non-inverting
lossless integrator and an inverting second order low-pass filter. The
oscillation condition and oscillation frequency can be
electronically/orthogonally controlled via input bias currents. The
circuit description is very simple, consisting of merely 1 DDCC, 1
VDTA, 1 grounded resistor and 3 grounded capacitors. Using only
grounded elements, the proposed circuit is then suitable for IC
architecture. The proposed oscillator has high output impedance
which is easy to cascade or dive the external load without the buffer
devices. The PSPICE simulation results are depicted, and the given
results agree well with the theoretical anticipation. The power
consumption is approximately 1.76mW at ±1.25V supply voltages.