In this work, an original Sallen-Key second-order low-pass filter is first turned into a current-mode one by means of the adjoint network theorem. Two nodal admittance matrices(NAM) of the filter are then educed. Furt...In this work, an original Sallen-Key second-order low-pass filter is first turned into a current-mode one by means of the adjoint network theorem. Two nodal admittance matrices(NAM) of the filter are then educed. Furthermore, these two matrices are expanded through NAM expansion approach, generating one current-mode Sallen-Key filter, which uses two compact voltage differential trans-conductance amplifiers(VDTAs) and two grounded capacitors, implements not only one low-pass transfer function but two band-pass transfer functions, and provides the non-interrelated control between the natural frequency and quality factor. As an example of the synthesized filter, a second-order VDTA filter with fo=1 MHz, Q=1, HLP=-HBP1=HBP2=1 is designed. The used synthesis approach has been confirmed with the help of circuit and computer analysis.展开更多
This paper designs a current-mode Wien-bridge oscillator to use current-controlled conveyor(CCCIIs)based on the traditional Wien-bridge oscillator and the adjoint network theorem.This oscillator employs only four CCCI...This paper designs a current-mode Wien-bridge oscillator to use current-controlled conveyor(CCCIIs)based on the traditional Wien-bridge oscillator and the adjoint network theorem.This oscillator employs only four CCCIIs and two grounded capacitors.Its resonant condition and resonant frequency can be independently and electronically varied by tuning bias currents of the CCCIIs linearly.Then this oscillator is simple in design,compact in size,and convenient in adjustment.The oscillator analysis and computer simulation results have been included to support the generation method.展开更多
基金the Natural Science Foundation of Shaanxi Province (2017JM6087)。
文摘In this work, an original Sallen-Key second-order low-pass filter is first turned into a current-mode one by means of the adjoint network theorem. Two nodal admittance matrices(NAM) of the filter are then educed. Furthermore, these two matrices are expanded through NAM expansion approach, generating one current-mode Sallen-Key filter, which uses two compact voltage differential trans-conductance amplifiers(VDTAs) and two grounded capacitors, implements not only one low-pass transfer function but two band-pass transfer functions, and provides the non-interrelated control between the natural frequency and quality factor. As an example of the synthesized filter, a second-order VDTA filter with fo=1 MHz, Q=1, HLP=-HBP1=HBP2=1 is designed. The used synthesis approach has been confirmed with the help of circuit and computer analysis.
基金the Natural Science Foundation of Shaanxi Province(2017JM6087)。
文摘This paper designs a current-mode Wien-bridge oscillator to use current-controlled conveyor(CCCIIs)based on the traditional Wien-bridge oscillator and the adjoint network theorem.This oscillator employs only four CCCIIs and two grounded capacitors.Its resonant condition and resonant frequency can be independently and electronically varied by tuning bias currents of the CCCIIs linearly.Then this oscillator is simple in design,compact in size,and convenient in adjustment.The oscillator analysis and computer simulation results have been included to support the generation method.