Design Of Continuous-time Integrated Filters: CCⅡ, FTFN And CFA

The design of full integrated continuous-time filters is one of the most important areas of development of analog very large scale integrated circuits in recent years; it is also an advanced subject of study in the contemporary world.using current conveyor, four-terminal floating nullor, current feedback amplifier as active devices,The design methods of low-order/high-order voltage-mode or current-mode integrated filters and oscillators are systematically expounded.The main contributions are as follows:1. Several current conveyor functional circuits such as simulated inductors, the first-order slope equilibrator and the first-order phase equilibrator are presented. The E type frequency dependent negative resistor, capacitor multipliers, analog multiplier and amplitude modulation using current conveyor are first presented.2. A series of voltage(current)-mode biquadratic filters which can realize lowpass, highpass, bandpass, allpass and notch filtering ruction respectively are designed.3. The design methods of the high-order lowpass, highpass, notch filters are presented using grounded simulated inductor, floating grounded simulated inductor. D type frequence dependent negative resistor based on CCII+/- to simulate high-order passive LC ladder networks. The design method of high-order highpass filters are first presented using E type frequence dependent negative resistor or generalized gyratyor based on CCII+-/-, PSPICE simulation results are obtained to verify the theoretical analyses.4. The general structure frame and principle of current-mode Nth-order lowpass / highpass filter is presented using multiple outputs current controlled conveyor( CCCII + ), The design method is illustrated by design examples. All the filter architectures contain only grounded capacitors or grounded inductors. It is convenient to circuit's integration, and a general conclusion for sensitivity analysis is formulated.5. A universal voltage-mode second-order filter and a current-mode multi-function second-order filter based on four-terminal floating nullor are presented, Sensitivity analysis results show that both the circuits enjoy low passive sensitivities and active sensitivities.6. Some new voltage-mode second-order filters based on current feedback amplifier are proposed. The major merits of these circuits are multiple filtering function and adjustable parameter. The signal flow graph method of high-order lowpass filter with low sensitivities is presented.7. Two kinds of sinusoidal oscilltors based on allpass filter and bandpass filter are designed by leading sinusoidal oscilltor design principle based on filter into sinusoidal oscilltors constructed current conveyors. Three-phase and fifth-phase sinusoidal oscilltors based on current feedback amplifier are first presented. In the light of relaxation oscillator consisted of current-mode Shmitt trigger and multiple outputs current controlled conveyor, Theory research and computer simulation are conducted. The results show both of them is unanimous.