Jiří Sedláček

Current conveyor with very low output impedance voltage buffer for laboratory instrumentation

This paper presents the design and implementation of second generation current conveyor CCII- in 0.35µm CMOS process. In the design, we intended to achieve very low output impedance of voltage buffer over wide frequency range, in order to comply with high requirements for laboratory instrumentation. Selected approach relies on the optimization of voltage buffer, which is composed of minimal amount of transistors. This allows considerably reducing all parasitic capacitances in the circuit and achieving very low output impedance in units of ohms at frequencies up to 10 MHz. In addition, the solution exhibits high driving capability of both X and Z output terminals.

General multiple LC prototype filter solutions and optimization

New possibilities of optimization of LC filter prototypes are presented in this paper. This optimization of LC filter prototypes is also useful for design of ARC and SC filters. The contribution describes various filter design procedures, which enables us to generate multiple filter solutions by means a traditional synthesis method. In comparison to other published methods, the presented procedures offer wider possibilities of multiple filter solutions using easy methods. A sensitivity comparison of generated multiple solutions is also shown. Some possibilities of filter element spread minimization as well as the filter tolerance design optimization are briefly documented in some examples of low-pass filter prototypes.