Capacitor Multiplier With Wide Dynamic Range and Large Multiplication Factor for Filter Applications

A capacitor multiplier realization based on current-voltage conversion with a high-performance voltage follower is presented. The architecture has a large multiplication factor of up to 10 000 or larger compared with current-mode multipliers, and a wide dynamic range compared with voltage-mode capacitor multipliers. It offers higher accuracy than voltage-mode multipliers as the design is based on passive devices, eliminating the variations of the drain-source output resistance of a transistor. The structure offers a very low equivalent series resistance, and it proved to be useful for low-voltage applications. Experimental results of a test chip in 0.5-μm CMOS technology implemented in low-pass and bandpass filters that validate the operation are presented.