Current-mode oscillators using single current follower

Abstract

References prediction* from the above cited parameters and an assumed amplifier excess spontaneous emission factor of 1.4.We report two sets of BER measurements in Fig. 2. The first, carried out with the loop exactly as described above, and , , ' -1 0 1:

CMOS digitally programmable quadrature oscillators

“…Also, the condition of oscillation can be independently tuned by varying 3 . In addition, it can be shown that the output voltages (V 1 and V 2 ) and currents (I 1 and I 2 ) are in quadrature and will have equal amplitudes when C 1 = C 2 , R 1 = R 2 and 1 = 2 .…”

“…Sinusoidal oscillator designs using the current-mode (CM) approach have gained considerable attention. Among these circuits, oscillators based on current followers (CFs) and/or voltage followers (VFs) such as those of [2][3][4][5][6][7] seem to be attractive. This stems from the high-frequency operation and low power consumption of the unity gain cells [8].…”

“…The circuit of [2] is an N-phase oscillator but it cannot provide quadrature oscillation since N must be odd to sustain oscillation. Some circuits of [3][4][5] can be modified to 954 H. A. ALZAHER provide CM quadrature oscillations. This could be achieved if two additional CFs were used to sense the currents flowing through a parallel pair of grounded resistor and capacitor.…”

“…The error in the phase difference will increase as the frequency increases where r x will dominate the impedance of the capacitor. Moreover, the circuits of [4] are single tune oscillators and those of [3,5] require simultaneous change of two or more passive elements in order to vary the frequency of oscillation. Several single resistance-controlled oscillators including two VM quadrature oscillators are presented in [7].…”

Electronically Controllable Explicit Current Output Sinusoidal Oscillator Employing Single VDTA

“…Sinusoidal oscillators find numerous applications in communication, control systems, signal processing, instrumentation, and measurement systems; see [3][4][5] and the references cited therein. Explicit current-mode sinusoidal oscillators (ECMSOs) based upon different active single building blocks are available in the literature; see [6][7][8][9][10][11][12][13] and the references cited therein.…”