Research On CCCDBA And Its Filters

The paper mainly studies on the principle, design and applications of current controlled current differencing buffered amplifier(CCCDBA). Firstly, it introduces the development and character of the current-mode circuit, and compares current-mode circuit with voltage-mode circuit simply. Afterwards, the development, character and port characteristic of the current differencing buffered amplifier(CDBA) are introduced. Then, it introduces the realization method and character of CDBA circuit and characteristic of each implementation briefly:combination with standard block circuit, configuration in bipolar junction transistor(BJT) process, configuration in CMOS process and realized using BiCMOS process.Then, the principle of controllrable and simple application of CDBA has been described. Finally, based on existed CCCDBA,we present two novel CCCDBA, CMOS compound transistor CCCDBA, and dual-differencing-input multiple-output CCCDBA, the application of CCCDBA which has been proposed in the design of analog filter is presented in detail.The main contents are as follows:(1) A new CMOS compound transistor CCCDBA is presented in this paper. The proposed circuit eliminates the drawback of rigor MOS size condition of traditional CMOS CDBA which can be controllrable, therefore it is easy to be realized. Combining the proposed circuit block with the current devision technique,the paper design a new digital-tunable analog filter, its Q and pole frequency can be tuned respectively, which extend the analog filter to digital-tunable domain. Toward whether new compound transistor CCCDBA or its constructed digital-tunable filter, simulated by PSPICE with Chartered 0.5μm technology verify its performance .(2) A new dual-diferencing-input multiple-output BJT-type CCCDBA is presented in this paper. The proposed circuit has two couple of differencing-input ports, two current-output and tow voltage-output ports, work out at eight ports, therefore it can straight output and feed back to input simultaneously, simplified designing application circuit. A novel both floating and grounded negative inductance simulators and a universal biquadratic filter are comprised with circuit block which has been presented in this paper is verified. The all application circuit of the circuit block has property of simple construct,electronic-tunable and easy to fully-integrated. Simulated by PSPICE show good agreement to theoretical anticipation.(3) A universal design method based on current-mode CCCDBA ladder filters is proposed. Using the proposed dual-diferencing-input multiple-output CCCDBA to simulate RLC ladder prototypes, a high-order active analog filters can be realized. The filter has advantages of low sensitivity, high accuracy, electronic-controllable, and it is easy to fully-integrated. Simulated by PSPICE show it is a high performance high-order filter compared others fiters which realized in same methods.