Current‐mode quadrature oscillator using current differencing transconductance amplifiers

Multi-function Current Differencing Cascaded Transconductance Amplifier (MCDCTA) and Its Application to Current-Mode Multiphase Sinusoidal Oscillator

“…Comparing some others active device, the outstanding features of this active element are larger dynamic range, high slew rate, electronic adjustability and low-input and high-output impedance etc. Meanwhile, from our investigations, CDTA element and its some modified devices have been widely used in analog signal processing circuit in recently years [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. However, so far, all of the reported CDTAs have two unavoidable problems: first, the transconductanse of the CDTA can not linearly tunable by controlling external bias current in a large input current range.…”

Allpass section-based mixed-mode quadrature sinusoidal oscillator

“…Our survey found that several active components have been used to realize this type of oscillator such as current conveyor transconductance amplifier (CCTA) [12], current differencing transconductance amplifier [13]- [15], differencing voltage current conveyor (DVCC) [16], and zcopy current follower transconductance amplifier (ZC-CFTA) [15]. However, the studies in [12]- [15] require an external resistor. Although, the circuits in [16], [17] enjoy resistor-less and independent control of the CO and FO but they still use many active components, i.e.…”

Multifunction Current Differencing Cascaded Transconductance Amplifier (MCDCTA) and Its Application to Current-Mode Multiphase Sinusoidal Oscillator

“…Comparing some others active device, the outstanding features of this active element are larger dynamic range, high slew rate, electronic adjustability and low-input and high-output impedance etc. Meanwhile, from our investigations, CDTA element and its some modified devices have been widely used in analog signal processing circuit in recently years [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. However, so far, all of the reported CDTAs have two unavoidable problems: first, the transconductance of the CDTA cannot linearly tunable by controlling external bias current in a large input current range.…”