Active capacitance multipliers using current conveyors

One of the most limiting problems in the design of integrated circuits is constituted by the realization of high valued capacitors, who have the heavy drawback of high occupation of silicon area. Moreover, in some sensor applications, it can be useful to deal with capacitance values higher than those normally given by capacitive sensors. In these cases, the use of capacitance multipliers can be very important. In this paper, we propose a novel principle of simple capacitance multipliers, by which it is possible to obtain higher capacitive values. Two solutions, the first using one CCII- with current gain and the second using two conventional CCIIs, are presented and analyzed. The effects of CCII non-idealities are also evaluated and discussed. Finally, SPICE simulations, which are in a close agreement with the analytical calculations, are also reported.

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